Condensed Consolidated Statement of Stockholders' Equity (USD $) In Thousands	Total	Common stock	Additional Paid-in Capital	Retained Earnings	Accumulated Other Comprehensive Loss	Treasury Stock	Non-Controlling Interest
Beginning Balance at Dec. 31, 2010	$ 1,138,914	$ 74	$ 752,803	$ 294,316		$ (10,831)	$ 102,552
Beginning Balance (in shares) at Dec. 31, 2010		73,930
Shares issued on exercise of stock options and warrants (in shares)		567
Shares issued on exercise of stock options and warrants	2,352	1	2,351
Shares issued on vesting of restricted stock		218
Shares issued for earn-out on acquisition (in shares)		144
Shares issued for earn-out on acquisition	427		427
Tax benefit of stock option exercises	3,352		3,352
Compensation expense in connection with restricted stock and stock options	7,321		7,321
Cost of shares repurchased on vesting of restricted stock and exercise of stock options	(2,612)					(2,612)
Equity portion of convertible notes	33,875		33,875
Net cost of hedge on convertible notes	(9,374)		(9,374)
Comprehensive income:
Net income	110,999			98,943			12,056
Change in fair value of hedges	(483)				(483)
Total comprehensive income	110,516
Distributions to joint ventures	(27,495)						(27,495)
Non-controlling interest of acquired companies	14,930						14,930
Ending Balance at Sep. 30, 2011	$ 1,272,206	$ 75	$ 790,755	$ 393,259	$ (483)	$ (13,443)	$ 102,043
Ending Balance (in shares) at Sep. 30, 2011		74,859