Consolidated statement of stockholders' equity (USD $) In Thousands, except Share data, unless otherwise specified	Total	Common Stock	Additional paid-in capital	Treasury Stock (at cost)	Accumulated deficit
Balance, beginning of period at Dec. 31, 2013	$ 1,272,256	$ 1,427	$ 1,283,809	$ 0	$ (12,980)
Balance, beginning of period (in shares) at Dec. 31, 2013		142,671,000		0
Increase (Decrease) in Stockholders' Equity
Restricted stock awards		12	(12)
Restricted stock awards (in shares)		1,161,000
Restricted stock forfeitures		(1)	1
Restricted stock forfeitures (in shares)		(50,000)
Vested restricted stock exchanged for tax withholding	(3,556)			(3,556)
Vested restricted stock exchanged for tax withholding (in shares)				136,000
Retirement of treasury stock		(2)	(3,554)	3,556
Retirement of treasury stock (in shares)		(136,000)		(136,000)
Exercise of employee stock options	1,829	1	1,828
Exercise of employee stock options (in shares)		91,000
Stock-based compensation	12,892		12,892
Net loss	(19,112)				(19,112)
Balance, end of period (in shares)		143,737,000		0
Balance, end of period at Jun. 30, 2014	$ 1,264,309	$ 1,437	$ 1,294,964	$ 0	$ (32,092)