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 Income	Treasury Stock	Noncontrolling Interest
Beginning Balance at Dec. 31, 2014	$ 1,050,643	$ 79	$ 948,714	$ 805,526	$ (24,186)	$ (812,429)	$ 132,939
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	$ 0	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
Purchase of minority interest in consolidated joint venture	$ (6,000)		750				(6,750)
Shares issued on exercise of stock options and warrants	0	$ 0
Tax benefit of stock option exercises	98		98
Compensation expense in connection with restricted stock	9,824		9,824
Shares repurchased cost method	(12,391)					(12,391)
Shares repurchased cost method	(12,359)					(12,359)
Change in redemption value of redeemable non-controlling interest	(537)		(537)
Change in fair value of available for sale securities	299				299
Net income	83,166			72,129			11,037
Foreign currency translation gain (loss)	(27,066)				(27,066)
Distributions to joint ventures	(13,695)						(13,695)
Non-controlling interest of acquired companies	12,333						12,333
Ending Balance at Sep. 30, 2015	$ 1,100,019	$ 80	$ 974,552	$ 877,655	$ (50,953)	$ (837,179)	$ 135,864
Ending Balance (in shares) at Sep. 30, 2015		80,491,000