CONSOLIDATED STATEMENTS OF CHANGES IN EQUITY (UNAUDITED) - USD ($) $ in Thousands |
Total |
Common Stock [Member] |
Additional Paid-in Capital [Member] |
Accumulated Deficit [Member] |
Cost of Shares Held in Treasury [Member] |
Accumulated Other Comprehensive Loss [Member] |
Noncontrolling Interests [Member] |
Redeemable Noncontrolling Interests [Member] |
Balances at Dec. 31, 2017 |
$ 1,418,144
|
$ 2,069
|
$ 2,374,006
|
$ (1,079,472)
|
$ (6,865)
|
$ (108,542)
|
$ 236,948
|
|
Balances (in shares) at Dec. 31, 2017 |
|
206,877,037
|
|
|
|
|
|
|
Equity [Roll Forward] |
|
|
|
|
|
|
|
|
Non-cash and stock-based compensation |
23,320
|
|
23,320
|
|
|
|
|
|
Common Stock issued under stock plans, net of shares withheld for employee taxes |
(8,602)
|
$ 4
|
(8,606)
|
|
|
|
|
|
Common stock issued under stock plans, net of shares withheld for employee taxes (in shares) |
|
359,817
|
|
|
|
|
|
|
Exercise of stock options, net of shares withheld for option cost and employee taxes |
10,854
|
$ 6
|
10,848
|
|
|
|
|
|
Exercise of stock options (in shares) |
|
632,981
|
|
|
|
|
|
|
Fair value of convertible debt conversion feature, net of issuance costs |
62,624
|
|
62,624
|
|
|
|
|
|
Repurchase of convertible debt conversion feature |
(92,641)
|
|
(92,641)
|
|
|
|
|
|
Acquisitions |
22,404
|
|
|
|
|
|
22,404
|
|
Purchases of noncontrolling interests |
73
|
|
1,709
|
|
|
|
(1,636)
|
|
Redeemable noncontrolling interests fair value adjustments |
(33,456)
|
|
(33,456)
|
|
|
|
|
|
Contributions received |
4,900
|
|
|
|
|
|
4,900
|
|
Cash distributions |
(23,269)
|
|
|
|
|
|
(23,269)
|
|
Other |
(2,571)
|
|
(113)
|
|
|
|
(2,458)
|
|
Comprehensive income (loss): |
|
|
|
|
|
|
|
|
Net income |
41,035
|
|
|
35,453
|
|
|
5,582
|
|
Foreign currency translation adjustments |
(17,295)
|
|
|
|
|
(17,295)
|
|
|
Balances at Jun. 30, 2018 |
1,405,520
|
$ 2,079
|
2,337,691
|
(1,044,019)
|
(6,865)
|
(125,837)
|
242,471
|
|
Balances (in shares) at Jun. 30, 2018 |
|
207,869,835
|
|
|
|
|
|
|
Balances at Dec. 31, 2017 |
|
|
|
|
|
|
|
$ 244,727
|
Redeemable Noncontrolling Interests [Roll Forward] |
|
|
|
|
|
|
|
|
Acquisitions |
|
|
|
|
|
|
|
21,870
|
Purchases of noncontrolling interests |
|
|
|
|
|
|
|
(356)
|
Redeemable noncontrolling interests fair value adjustments |
|
|
|
|
|
|
|
33,456
|
Contributions received |
|
|
|
|
|
|
|
0
|
Cash distributions |
|
|
|
|
|
|
|
(7,874)
|
Other |
|
|
|
|
|
|
|
78
|
Comprehensive income (loss): |
|
|
|
|
|
|
|
|
Net income |
|
|
|
|
|
|
|
1,293
|
Balances at Jun. 30, 2018 |
|
|
|
|
|
|
|
293,194
|
Balances at Mar. 31, 2018 |
1,372,221
|
$ 2,076
|
2,348,118
|
(1,113,378)
|
(6,865)
|
(92,280)
|
234,550
|
|
Balances (in shares) at Mar. 31, 2018 |
|
207,634,062
|
|
|
|
|
|
|
Equity [Roll Forward] |
|
|
|
|
|
|
|
|
Non-cash and stock-based compensation |
12,450
|
|
12,450
|
|
|
|
|
|
Common Stock issued under stock plans, net of shares withheld for employee taxes |
(656)
|
$ 1
|
(657)
|
|
|
|
|
|
Common stock issued under stock plans, net of shares withheld for employee taxes (in shares) |
|
72,008
|
|
|
|
|
|
|
Exercise of stock options, net of shares withheld for option cost and employee taxes |
2,932
|
$ 2
|
2,930
|
|
|
|
|
|
Exercise of stock options (in shares) |
|
163,765
|
|
|
|
|
|
|
Repurchase of convertible debt conversion feature |
(9,225)
|
|
(9,225)
|
|
|
|
|
|
Acquisitions |
8,955
|
|
|
|
|
|
8,955
|
|
Purchases of noncontrolling interests |
0
|
|
1,143
|
|
|
|
(1,143)
|
|
Redeemable noncontrolling interests fair value adjustments |
(16,924)
|
|
(16,924)
|
|
|
|
0
|
|
Cash distributions |
(6,992)
|
|
|
|
|
|
(6,992)
|
|
Other |
(2,611)
|
|
(144)
|
|
|
|
(2,467)
|
|
Comprehensive income (loss): |
|
|
|
|
|
|
|
|
Net income |
78,927
|
|
|
69,359
|
|
|
9,568
|
|
Foreign currency translation adjustments |
(33,557)
|
|
|
|
|
(33,557)
|
|
|
Balances at Jun. 30, 2018 |
1,405,520
|
$ 2,079
|
2,337,691
|
(1,044,019)
|
(6,865)
|
(125,837)
|
242,471
|
|
Balances (in shares) at Jun. 30, 2018 |
|
207,869,835
|
|
|
|
|
|
|
Balances at Mar. 31, 2018 |
|
|
|
|
|
|
|
264,700
|
Redeemable Noncontrolling Interests [Roll Forward] |
|
|
|
|
|
|
|
|
Acquisitions |
|
|
|
|
|
|
|
11,689
|
Purchases of noncontrolling interests |
|
|
|
|
|
|
|
2
|
Redeemable noncontrolling interests fair value adjustments |
|
|
|
|
|
|
|
16,924
|
Cash distributions |
|
|
|
|
|
|
|
(4,628)
|
Other |
|
|
|
|
|
|
|
78
|
Comprehensive income (loss): |
|
|
|
|
|
|
|
|
Net income |
|
|
|
|
|
|
|
4,429
|
Balances at Jun. 30, 2018 |
|
|
|
|
|
|
|
293,194
|
Balances at Dec. 31, 2018 |
1,342,743
|
$ 2,091
|
2,268,209
|
(1,019,223)
|
(6,865)
|
(145,231)
|
243,762
|
|
Balances (in shares) at Dec. 31, 2018 |
|
209,135,581
|
|
|
|
|
|
|
Equity [Roll Forward] |
|
|
|
|
|
|
|
|
Non-cash and stock-based compensation |
24,992
|
|
24,992
|
|
|
|
|
|
Common Stock issued under stock plans, net of shares withheld for employee taxes |
(10,259)
|
$ 3
|
(10,262)
|
|
|
|
|
|
Common stock issued under stock plans, net of shares withheld for employee taxes (in shares) |
|
312,857
|
|
|
|
|
|
|
Exercise of stock options, net of shares withheld for option cost and employee taxes |
10,199
|
$ 7
|
10,192
|
|
|
|
|
|
Exercise of stock options (in shares) |
|
637,377
|
|
|
|
|
|
|
Conversion of convertible debt |
28,586
|
$ 0
|
28,586
|
|
|
|
|
|
Conversion of convertible debt (in shares) |
|
824,328
|
|
|
|
|
|
|
Acquisitions |
26,168
|
|
|
|
|
|
26,168
|
|
Purchases of noncontrolling interests |
0
|
|
270
|
|
|
|
(270)
|
|
Redeemable noncontrolling interests fair value adjustments |
(25,827)
|
|
(25,827)
|
|
|
|
|
|
Contributions received |
8,324
|
|
|
|
|
|
8,324
|
|
Cash distributions |
(52,115)
|
|
|
|
|
|
(52,115)
|
|
Other |
(1,411)
|
|
(150)
|
|
|
|
(1,261)
|
|
Comprehensive income (loss): |
|
|
|
|
|
|
|
|
Net income |
59,916
|
|
|
50,911
|
|
|
9,005
|
|
Foreign currency translation adjustments |
(3,560)
|
|
|
|
|
(3,560)
|
|
|
Balances at Jun. 30, 2019 |
1,407,756
|
$ 2,101
|
2,296,010
|
(968,312)
|
(6,865)
|
(148,791)
|
233,613
|
|
Balances (in shares) at Jun. 30, 2019 |
|
210,910,143
|
|
|
|
|
|
|
Balances at Dec. 31, 2018 |
329,355
|
|
|
|
|
|
|
329,355
|
Redeemable Noncontrolling Interests [Roll Forward] |
|
|
|
|
|
|
|
|
Acquisitions |
|
|
|
|
|
|
|
39,303
|
Purchases of noncontrolling interests |
|
|
|
|
|
|
|
(1,459)
|
Redeemable noncontrolling interests fair value adjustments |
|
|
|
|
|
|
|
25,827
|
Contributions received |
|
|
|
|
|
|
|
0
|
Cash distributions |
|
|
|
|
|
|
|
(11,258)
|
Other |
|
|
|
|
|
|
|
2,597
|
Comprehensive income (loss): |
|
|
|
|
|
|
|
|
Net income |
|
|
|
|
|
|
|
963
|
Balances at Jun. 30, 2019 |
385,328
|
|
|
|
|
|
|
385,328
|
Balances at Mar. 31, 2019 |
1,240,394
|
$ 2,099
|
2,267,761
|
(1,071,667)
|
(6,865)
|
(148,120)
|
197,186
|
|
Balances (in shares) at Mar. 31, 2019 |
|
209,857,816
|
|
|
|
|
|
|
Equity [Roll Forward] |
|
|
|
|
|
|
|
|
Non-cash and stock-based compensation |
11,754
|
|
11,754
|
|
|
|
|
|
Common Stock issued under stock plans, net of shares withheld for employee taxes |
(959)
|
$ 0
|
(959)
|
|
|
|
|
|
Common stock issued under stock plans, net of shares withheld for employee taxes (in shares) |
|
60,223
|
|
|
|
|
|
|
Exercise of stock options, net of shares withheld for option cost and employee taxes |
2,527
|
$ 2
|
2,525
|
|
|
|
|
|
Exercise of stock options (in shares) |
|
167,776
|
|
|
|
|
|
|
Conversion of convertible debt |
28,586
|
$ 0
|
28,586
|
|
|
|
|
|
Conversion of convertible debt (in shares) |
|
824,328
|
|
|
|
|
|
|
Acquisitions |
25,194
|
|
|
|
|
|
25,194
|
|
Purchases of noncontrolling interests |
0
|
|
0
|
|
|
|
0
|
|
Redeemable noncontrolling interests fair value adjustments |
(13,515)
|
|
(13,515)
|
|
|
|
|
|
Contributions received |
8,324
|
|
|
|
|
|
8,324
|
|
Cash distributions |
(6,172)
|
|
|
|
|
|
(6,172)
|
|
Other |
(219)
|
|
(142)
|
|
|
|
(77)
|
|
Comprehensive income (loss): |
|
|
|
|
|
|
|
|
Net income |
112,513
|
|
|
103,355
|
|
|
9,158
|
|
Foreign currency translation adjustments |
(671)
|
|
|
|
|
(671)
|
|
|
Balances at Jun. 30, 2019 |
1,407,756
|
$ 2,101
|
$ 2,296,010
|
$ (968,312)
|
$ (6,865)
|
$ (148,791)
|
$ 233,613
|
|
Balances (in shares) at Jun. 30, 2019 |
|
210,910,143
|
|
|
|
|
|
|
Balances at Mar. 31, 2019 |
|
|
|
|
|
|
|
343,029
|
Redeemable Noncontrolling Interests [Roll Forward] |
|
|
|
|
|
|
|
|
Acquisitions |
|
|
|
|
|
|
|
32,322
|
Purchases of noncontrolling interests |
|
|
|
|
|
|
|
0
|
Redeemable noncontrolling interests fair value adjustments |
|
|
|
|
|
|
|
13,515
|
Contributions received |
|
|
|
|
|
|
|
0
|
Cash distributions |
|
|
|
|
|
|
|
(7,317)
|
Other |
|
|
|
|
|
|
|
172
|
Comprehensive income (loss): |
|
|
|
|
|
|
|
|
Net income |
|
|
|
|
|
|
|
3,607
|
Balances at Jun. 30, 2019 |
$ 385,328
|
|
|
|
|
|
|
$ 385,328
|