Consolidated Statements of Equity - USD ($) $ in Thousands	Total	Class A Common Stock [Member]	Additional Paid-In Capital [Member]	Accumulated Earnings [Member]	Minimum pension liability [Member]	Foreign currency translation and other [Member]	Non-controlling Interests [Member]
Beginning balance at Dec. 31, 2013	$ 1,936,006	$ 3,319	$ 981,997	$ 1,056,592	$ (75,307)	$ (70,816)	$ 40,221
Beginning balance (in shares) at Dec. 31, 2013		331,927,166
Net income	513,503			484,503			29,000
Pension liability adjustments, net of tax	(30,355)				(30,355)
Stock options exercised	7,421	$ 5	7,416
Stock options exercised (including tax benefit) (in shares)		458,505
Restricted stock awards vesting	6,794	$ 9	6,785
Restricted stock awards vesting (in shares)		887,975
Compensation expense for equity awards	59,757		59,757
Shares and units repurchased for payment of taxes on equity awards	(16,685)	$ (2)	(16,683)
Shares repurchased for payment of taxes on stock awards (in shares)		(242,461)
Amounts reclassified from accumulated other comprehensive loss to interest expense, net of tax	7,279					7,279
Unrealized losses on interest rate swaps and interest rate caps, net of tax	(5,927)					(5,927)
Unrealized holding (losses) gains on available for sale securities, net of tax	(941)					(941)
Foreign currency translation (loss) gain	(148,589)					(148,502)	(87)
Cancellation of non-vested stock awards	(1)	$ (1)
Cancellation of non-vested stock awards (in shares)		(45,109)
Contributions from non-controlling interests	2,938						2,938
Distributions to non-controlling interests	(33,971)						(33,971)
Other	4,169		153			549	3,467
Other (in shares)		4,955
Ending balance at Dec. 31, 2014	2,301,398	$ 3,330	1,039,425	1,541,095	(105,662)	(218,358)	41,568
Ending balance (in shares) at Dec. 31, 2014		332,991,031
Net income	558,877			547,132			11,745
Pension liability adjustments, net of tax	3,741				3,741
Stock options exercised	9,802	$ 6	9,796
Stock options exercised (including tax benefit) (in shares)		561,583
Restricted stock awards vesting	6,724	$ 10	6,714
Restricted stock awards vesting (in shares)		1,021,950
Compensation expense for equity awards	74,709		74,709
Shares and units repurchased for payment of taxes on equity awards	(24,523)	$ (3)	(24,520)
Shares repurchased for payment of taxes on stock awards (in shares)		(332,799)
Fees associated with termination of interest rate swaps, net of tax (see Note 6)	(3,908)					(3,908)
Amounts reclassified from accumulated other comprehensive loss to interest expense, net of tax	7,680					7,680
Unrealized losses on interest rate swaps and interest rate caps, net of tax	(4,107)					(4,107)
Unrealized holding (losses) gains on available for sale securities, net of tax	(705)					(705)
Foreign currency translation (loss) gain	(164,350)					(164,359)	9
Cancellation of non-vested stock awards	(1)	$ (1)
Cancellation of non-vested stock awards (in shares)		(13,338)
Contributions from non-controlling interests	5,909						5,909
Distributions to non-controlling interests	(16,582)						(16,582)
Other	4,406		634			3	3,769
Other (in shares)		2,069
Ending balance at Dec. 31, 2015	2,759,070	$ 3,342	1,106,758	2,088,227	(101,921)	(383,754)	46,418
Ending balance (in shares) at Dec. 31, 2015		334,230,496
Net income	584,064			571,973			12,091
Pension liability adjustments, net of tax	(63,749)				(63,749)
Stock options exercised	915	$ 1	914
Stock options exercised (including tax benefit) (in shares)		89,727
Restricted stock awards vesting		$ 30	(30)
Restricted stock awards vesting (in shares)		2,955,142
Compensation expense for equity awards	63,484		63,484
Shares and units repurchased for payment of taxes on equity awards	(27,426)		(27,426)
Shares repurchased for payment of taxes on stock awards (in shares)		0
Amounts reclassified from accumulated other comprehensive loss to interest expense, net of tax	6,839					6,839
Unrealized losses on interest rate swaps and interest rate caps, net of tax	(1,431)					(1,431)
Unrealized holding (losses) gains on available for sale securities, net of tax	384					384
Foreign currency translation (loss) gain	(235,278)					(235,295)	17
Contributions from non-controlling interests	2,272						2,272
Distributions to non-controlling interests	(19,133)						(19,133)
Other	(14,447)		(3,449)			(12,091)	1,093
Other (in shares)		4,084
Ending balance at Dec. 31, 2016	3,057,245	$ 3,373	1,145,226	2,656,906	$ (165,670)	$ (625,348)	$ 42,758
Ending balance (in shares) at Dec. 31, 2016		337,279,449
Adoption of Accounting Standards Update 2016-09, net of tax (see Note 2)	$ 1,681		$ 4,975	$ (3,294)