Consolidated Statement of Stockholders' Equity (Unaudited) (USD $) In Thousands, except Share data	Total	Common Stock	Additional Paid In Capital	Treasury Stock	Accumulated Other Comprehensive Income (Loss)	Retained Earnings
Beginning balance at Dec. 31, 2010	$ 593,270	$ 1,166	$ 765,326	$ (2,657)	$ (9)	$ (170,556)
Beginning balance, shares at Dec. 31, 2010		116,564,000
Comprehensive income:
Net income (loss)	72,389					72,389
Unrealized gains (losses) on investments	(51)				(51)
Tax benefit (provisions)	0				0
Comprehensive income	72,338
Issuance of common stock	0	0	0
Issuance of common stock, shares		0
Exercises of employee stock options	582	1	581
Exercises of employee stock options, shares		69,000
Vesting of restricted stock		1	(1)
Vesting of restricted stock, shares		95,000
Stock based compensation	3,258		3,258
Stock based compensation, shares		8,000
Repurchases of common stock	(506)			(506)
Ending balance at Jun. 30, 2011	$ 668,942	$ 1,168	$ 769,164	$ (3,163)	$ (60)	$ (98,167)
Ending balance, shares at Jun. 30, 2011		116,736,000