Condensed Consolidated Statements of Stockholders' Equity (USD $) In Thousands, except Share data	Total	Common Stock	Additional Paid-In Capital	Retained Earnings	Accumulated Other Comprehensive Loss	Treasury Stock	Non-Controlling Interest
Beginning Balance at Dec. 31, 2014	$ 1,054,537	$ 79	$ 948,714	$ 809,420	$ (24,186)	$ (812,429)	$ 132,939
Beginning Balance (in shares) at Dec. 31, 2014		79,263,000
Issuance of common stock related acquisition of interest in joint venture (in shares)		465,000
Issuance of common stock related acquisition of interest in joint venture	15,703		15,703
Shares issued on vesting of restricted stock (in shares)		529,000
Shares issued on vesting of restricted stock	1	1
Tax benefit of stock option exercises	54		54
Compensation expense in connection with restricted stock	2,573		2,573
Shares repurchased on the open market	(6,980)					(6,980)
Cost of shares repurchased on vesting of restricted stock	(10,000)					(10,000)
Change in redemption value of redeemable non-controlling interest	(179)		(179)
Net income	65,907			62,840			3,067
Foreign currency translation	(38,239)				(38,239)
Distributions to joint ventures	(3,002)						(3,002)
Non-controlling interest of acquired companies	12,333						12,333
Ending Balance at Mar. 31, 2015	$ 1,092,708	$ 80	$ 966,865	$ 872,260	$ (62,425)	$ (829,409)	$ 145,337
Ending Balance (in shares) at Mar. 31, 2015		80,257,000