CONDENSED CONSOLIDATED STATEMENTS OF EQUITY (USD $) In Thousands, except Share data	Total	Common Stock [Member]	Additional Paid-In Capital [Member]	Accumulated Other Comprehensive Income (Loss) [Member]	Retained Earnings [Member]	Noncontrolling Interests [Member]
Balances at Dec. 31, 2010	$ 1,370,418	$ 1,139	$ 509,218	$ (3,095)	$ 858,887	$ 4,269
Balances, Shares at Dec. 31, 2010		113,950,081
Vesting of restricted stock units		5	(5)
Vesting of restricted stock units, Shares		538,878
Tax withholdings related to net share settlements of restricted stock units	(5,436)	(1)	(5,435)
Tax withholdings related to net share settlements of restricted stock units, Shares		(184,478)
Equity-based compensation	8,906		8,906
Exercise of stock options and warrants	4,956	4	4,952
Exercise of stock options and warrants, Shares		383,082
Excess tax benefit associated with equity-based compensation	4,500		4,500
Repurchase of common stock	(85,068)	(28)	(85,040)
Repurchase of common stock, Shares	(2,823,235)	(2,823,235)
Cash dividends on common stock	(25,497)				(25,497)
Amounts reclassified into earnings, net of taxes	900			900
Changes in fair value of cash flow hedges, net of taxes	(1,117)			(1,117)
Distributions to noncontrolling interests	(675)					(675)
Fair value of noncontrolling interest associated with business acquired	251					251
Net income	127,983				127,281	702
Balances at Sep. 30, 2011	1,400,121	1,119	437,096	(3,312)	960,671	4,547
Balance, Shares at Sep. 30, 2011		111,864,328
Balances at Dec. 31, 2011	1,399,687	1,109	408,721	(3,480)	988,560	4,777
Balances, Shares at Dec. 31, 2011	110,907,782	110,907,782
Vesting of restricted stock units		6	(6)
Vesting of restricted stock units, Shares		588,910
Tax withholdings related to net share settlements of restricted stock units	(6,039)	(2)	(6,037)
Tax withholdings related to net share settlements of restricted stock units, Shares		(189,200)
Equity-based compensation	14,036		14,036
Exercise of stock options and warrants	1,042	1	1,041
Exercise of stock options and warrants, Shares		95,900
Issuance of common stock, net of issuance costs of $376	369,584	120	369,464
Issuance of common stock, net of issuance costs of $376, Shares		12,000,000
Excess tax benefit associated with equity-based compensation	3,415		3,415
Repurchase of common stock	(18,597)	(6)	(18,591)
Repurchase of common stock, Shares	(619,447)	(619,447)
Cash dividends on common stock	(32,182)				(32,182)
Amounts reclassified into earnings, net of taxes	347			347
Changes in fair value of cash flow hedges, net of taxes	(2,947)			(2,947)
Distributions to noncontrolling interests	(94)					(94)
Net income	123,574				123,104	470
Balances at Sep. 30, 2012	$ 1,851,826	$ 1,228	$ 772,043	$ (6,080)	$ 1,079,482	$ 5,153
Balance, Shares at Sep. 30, 2012	122,783,945	122,783,945