Consolidated Statement of Stockholders' Equity (unaudited) - USD ($) $ in Thousands	Total	Common Stock Class A Common Stock	Common Stock Class B Common Stock	Common Stock Class B-1 Common Stock	Additional Paid-in Capital	Stockholders' Accumulated Deficit	Accumulated other comprehensive loss	Non-Controlling Interests
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Cumulative-effective adjustment from adoption of Topic 842, net of tax | Adoption of Topic 842	$ 13,561					$ 4,957		$ 8,604
Shares beginning balance (in shares) at Dec. 31, 2018		115,047,000	171,261,000	12,329,000
Stockholders' equity beginning balance at Dec. 31, 2018	896,363	$ 1,151	$ 1,713	$ 123	$ 530,438	(20,920)	$ (7,755)	391,613
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net (loss) income	(175,278)					(64,783)		(110,495)
Foreign currency translation adjustment	(983)						(425)	(558)
Stock-based compensation	10,571				10,571
Exercise of stock options (in shares)		205,000
Exercise of stock options	1,385	$ 2			922		(7)	468
Restricted stock unit vesting, net of shares withheld to cover payroll taxes (in shares)		250,000
Restricted stock unit vesting, net of shares withheld to cover payroll taxes	(921)	$ 2			6		(5)	(924)
Unrealized loss on cash flow hedge, net of tax	0
Redemption of Class B Common Stock (in shares)		320,000	(320,000)
Redemption of Class B Common Stock	223	$ 3	$ (3)		1,124		(19)	(882)
Conversion of Class B-1 Common Stock (in shares)		12,329,000		(12,329,000)
Conversion of Class B-1 Common Stock		$ 123		$ (123)
Reclassification of foreign currency translation adjustment included in net loss	3,413						1,461	1,952
Tax distribution	(82)							(82)
Other	1,100				1,100
Shares ending balance (in shares) at Jun. 30, 2019		128,151,000	170,941,000	0
Stockholders' equity ending balance at Jun. 30, 2019	749,352	$ 1,281	$ 1,710	$ 0	544,161	(80,746)	(6,750)	289,696
Shares beginning balance (in shares) at Mar. 31, 2019		115,564,000	170,941,000	12,329,000
Stockholders' equity beginning balance at Mar. 31, 2019	799,781	$ 1,156	$ 1,710	$ 123	537,159	(63,844)	(4,099)	327,576
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net (loss) income	(50,526)					(16,902)		(33,624)
Foreign currency translation adjustment	(6,219)						(2,663)	(3,556)
Stock-based compensation	6,224				6,224
Exercise of stock options (in shares)		8,000
Exercise of stock options	375				174			201
Restricted stock unit vesting, net of shares withheld to cover payroll taxes (in shares)		250,000
Restricted stock unit vesting, net of shares withheld to cover payroll taxes	(921)	$ 2			6		(5)	(924)
Unrealized loss on cash flow hedge, net of tax	0
Conversion of Class B-1 Common Stock (in shares)		12,329,000		(12,329,000)
Conversion of Class B-1 Common Stock		$ 123		$ (123)
Reclassification of foreign currency translation adjustment included in net loss	40						17	23
Other	598				598
Shares ending balance (in shares) at Jun. 30, 2019		128,151,000	170,941,000	0
Stockholders' equity ending balance at Jun. 30, 2019	749,352	$ 1,281	$ 1,710	$ 0	544,161	(80,746)	(6,750)	289,696
Shares beginning balance (in shares) at Dec. 31, 2019		147,070,000	152,117,000
Stockholders' equity beginning balance at Dec. 31, 2019	346,788	$ 1,470	$ 1,522		606,966	(377,880)	(68)	114,778
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net (loss) income	96,265					103,071		(6,806)
Net (loss) income	97,573
Foreign currency translation adjustment	(8,102)						(3,985)	(4,117)
Stock-based compensation	10,202				10,202
Exercise of stock options (in shares)		58,000
Exercise of stock options	158	$ 1			158		(6)	5
Restricted stock unit vesting, net of shares withheld to cover payroll taxes (in shares)		365,000
Restricted stock unit vesting, net of shares withheld to cover payroll taxes	(693)	$ 3			178		(15)	(859)
Unrealized loss on cash flow hedge, net of tax	(72,432)						(35,622)	(36,810)
Tax distribution	(1,170)							(1,170)
Shares ending balance (in shares) at Jun. 30, 2020		147,493,000	152,117,000
Stockholders' equity ending balance at Jun. 30, 2020	371,016	$ 1,474	$ 1,522		617,504	(274,809)	(39,696)	65,021
Redeemable Non-Controlling Interests, beginning balance at Dec. 31, 2019	0
Increase (Decrease) in Temporary Equity [Roll Forward]
Net (loss) income	1,308
Redeemable non-controlling interests issued for acquisitions	11,475
Tax distribution	(403)
Redeemable Non-Controlling Interests, ending balance at Jun. 30, 2020	12,380
Shares beginning balance (in shares) at Mar. 31, 2020		147,311,000	152,117,000
Stockholders' equity beginning balance at Mar. 31, 2020	403,458	$ 1,472	$ 1,522		611,600	(262,813)	(33,405)	85,082
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net (loss) income	(24,164)					(11,996)		(12,168)
Net (loss) income	(23,944)
Foreign currency translation adjustment	(2,967)						(1,460)	(1,507)
Stock-based compensation	5,663				5,663
Exercise of stock options (in shares)		56,000
Exercise of stock options	153	$ 1			153		(6)	5
Restricted stock unit vesting, net of shares withheld to cover payroll taxes (in shares)		126,000
Restricted stock unit vesting, net of shares withheld to cover payroll taxes	(183)	$ 1			88		(15)	(257)
Unrealized loss on cash flow hedge, net of tax	(9,774)						(4,810)	(4,964)
Tax distribution	(1,170)							(1,170)
Shares ending balance (in shares) at Jun. 30, 2020		147,493,000	152,117,000
Stockholders' equity ending balance at Jun. 30, 2020	371,016	$ 1,474	$ 1,522		$ 617,504	$ (274,809)	$ (39,696)	$ 65,021
Redeemable Non-Controlling Interests, beginning balance at Mar. 31, 2020	12,563
Increase (Decrease) in Temporary Equity [Roll Forward]
Net (loss) income	220
Tax distribution	(403)
Redeemable Non-Controlling Interests, ending balance at Jun. 30, 2020	$ 12,380