Condensed, Consolidated Statements of Equity (Unaudited) - USD ($) shares in Thousands, $ in Thousands	Total	Common Stock	Additional Paid-In Capital	Retained Earnings	Accumulated Other Comprehensive Income	Noncontrolling Interests
Beginning Balances, shares at Dec. 31, 2014		82,937
Beginning Balances at Dec. 31, 2014	$ 1,211,621	$ 83	$ 155,802	$ 1,064,158	$ (19,397)	$ 10,975
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income (excludes $417 and $359 March 31, 2015 and $640 and $365 March 31, 2016 related to redeemable and mandatorily redeemable noncontrolling interests, respectively)	38,777			38,301		476
Other comprehensive income (excludes $195 for March 31, 2015 and $167 for March 31, 2016 related to mandatorily redeemable noncontrolling interests)	(15,485)				(15,208)	(277)
Formation of noncontrolling interests	(14)					(14)
Distribution to noncontrolling interests	(598)					(598)
Purchase of noncontrolling interests	(690)		(217)			(473)
Share-based compensation	4,132		4,132
Issuance of common stock under stock incentive plans, shares		76
Issuance of common stock under stock incentive plans	404		404
Stock repurchases, shares		(878)
Stock repurchases	(44,845)	$ (1)	(44,844)
Excess tax benefit from stock based compensation	791		791
Ending Balances, shares at Mar. 31, 2015		82,135
Ending Balances at Mar. 31, 2015	$ 1,194,093	$ 82	116,068	1,102,459	(34,605)	10,089
Beginning Balances, shares at Dec. 31, 2015	80,764	80,764
Beginning Balances at Dec. 31, 2015	$ 1,257,034	$ 81	19,708	1,275,207	(50,034)	12,072
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income (excludes $417 and $359 March 31, 2015 and $640 and $365 March 31, 2016 related to redeemable and mandatorily redeemable noncontrolling interests, respectively)	46,716			46,227		489
Other comprehensive income (excludes $195 for March 31, 2015 and $167 for March 31, 2016 related to mandatorily redeemable noncontrolling interests)	12,431				12,245	186
Distribution to noncontrolling interests	(637)					(637)
Purchase of noncontrolling interests	(3,730)		(1,821)			(1,909)
Share-based compensation	4,906		4,906
Issuance of common stock under stock incentive plans, shares		55
Issuance of common stock under stock incentive plans	286		286
Stock repurchases, shares		(18)
Stock repurchases	(843)		(843)
Excess tax benefit from stock based compensation	445		445
Other	$ (107)					(107)
Ending Balances, shares at Mar. 31, 2016	80,801	80,801
Ending Balances at Mar. 31, 2016	$ 1,316,501	$ 81	$ 22,681	$ 1,321,434	$ (37,789)	$ 10,094