Condensed, Consolidated Statements of Equity (Unaudited) (USD $) In Thousands	Total	Common Stock	Additional Paid-In Capital	Retained Earnings	Accumulated Other Comprehensive Income	Noncontrolling Interests
Beginning Balances at Dec. 31, 2012	$ 1,194,393	$ 88	$ 390,359	$ 791,209	$ 1,847	$ 10,890
Beginning Balances, shares at Dec. 31, 2012		88,372
Net income (excludes $928 and $992 for the six months ended June 30, 2013 and $417 and $739 for the six months ended June 30, 2014 related to redeemable and mandatorily redeemable noncontrolling interests, respectively)	73,363			72,147		1,216
Other comprehensive loss	(6,341)				(6,341)
Distribution to noncontrolling interests	(850)				0	(850)
Purchase of noncontrolling interests	(4,551)		(469)			(4,082)
Share-based compensation	7,419		7,419
Issuance of common stock under stock incentive plans, shares		560
Issuance of common stock under stock incentive plans	4,181	1	4,180
Stock repurchases, shares		(327)
Stock repurchases, value	(7,956)		(7,956)
Excess tax benefit from stock options	771		771
Ending Balances at Jun. 30, 2013	1,260,429	89	394,304	863,356	(4,494)	7,174
Ending Balances, shares at Jun. 30, 2013		88,605
Beginning Balances at Dec. 31, 2013	1,317,540	89	384,721	928,720	(6,190)	10,200
Beginning Balances, shares at Dec. 31, 2013	88,508	88,508
Net income (excludes $928 and $992 for the six months ended June 30, 2013 and $417 and $739 for the six months ended June 30, 2014 related to redeemable and mandatorily redeemable noncontrolling interests, respectively)	80,667			79,627		1,040
Other comprehensive loss	(712)
Other comprehensive loss (excludes $30 related to mandatorily redeemable noncontrolling interests).	(682)				(662)	(20)
Dissolution of noncontrolling interests	933					933
Distribution to noncontrolling interests	(970)					(970)
Purchase of noncontrolling interests	30		30
Share-based compensation	8,571		8,571
Issuance of common stock under stock incentive plans, shares		377
Issuance of common stock under stock incentive plans	467		467
Stock repurchases, shares		(1,471)
Stock repurchases, value	(49,091)	(2)	(49,089)
Excess tax benefit from stock options	2,092		2,092
Ending Balances at Jun. 30, 2014	$ 1,359,557	$ 87	$ 346,792	$ 1,008,347	$ (6,852)	$ 11,183
Ending Balances, shares at Jun. 30, 2014	87,414	87,414