Unaudited Condensed Consolidated Statements of Stockholders' Equity - 9 months ended Sep. 30, 2015 - USD ($) $ in Thousands	Total	Common Stock	Additional Paid-in Capital	Retained Earnings	Accumulated Other Comprehensive Loss	Treasury Stock	Noncontrolling Interest
Beginning Balance at Dec. 31, 2014	$ 951,437	$ 79	$ 940,922	$ 713,819	$ (24,186)	$ (812,429)	$ 133,232
Beginning Balance (in shares) at Dec. 31, 2014		79,263,000
Issuance of common stock related to acquisition of interest in joint venture (in shares)		465,000
Issuance of common stock related to acquisition of interest in joint venture	15,703		15,703
Shares issued on vesting of restricted stock (in shares)		748,000
Shares issued on vesting of restricted stock	$ 1	$ 1
Shares issued on exercise of stock options and warrants (in shares)	15,000	15,000
Shares issued on exercise of stock options and warrants	$ 245		245
Purchase of minority interest in consolidated joint venture	(6,000)		750				(6,750)
Tax benefit of stock option exercises	97		97
Compensation expense in connection with restricted stock	9,824		9,824
Shares repurchased cost method	(12,391)					(12,391)
Cost of shares repurchased on vesting of restricted stock and exercise of stock options	(12,604)					(12,604)
Change in redemption value of redeemable non-controlling interest, net of imputed interest	(3,763)			(3,763)
Change in fair value of available for sale securities	(650)				(650)
Change in non-controlling interest, net of imputed interest	3,356						3,356
Net income	87,046			73,711			13,335
Foreign currency translation gain (loss)	(26,560)				(26,560)
Distributions to joint ventures	(20,567)						(20,567)
Non-controlling interest of acquired companies	12,333						12,333
Ending Balance at Sep. 30, 2015	$ 997,507	$ 80	$ 967,541	$ 783,767	$ (51,396)	$ (837,424)	$ 134,939
Ending Balance (in shares) at Sep. 30, 2015		80,491,000