CONSOLIDATED STATEMENTS OF EQUITY (USD $) In Thousands, except Share data	Total	Common Stock [Member]	Additional Paid-in Capital [Member]	Treasury Stock [Member]	Retained Earnings [Member]	Accumulated Other Comprehensive Income (Loss) [Member]
Balances at beginning of period at Dec. 31, 2008	$ 960,601	$ 1,053	$ 1,690,851	$ (29,187)	$ (700,720)	$ (1,396)
Balances at beginning of period - shares (in share) at Dec. 31, 2008		105,256,000
Compensation expense related to restricted stock grants	26,935	0	26,935	0	0	0
Net loss	(66,255)	0	0	0	(66,255)	0
Issuance of common stock under Associate Stock Purchase Plan	1,007	1	1,006	0	0	0
Issuance of common stock under Associate Stock Purchase Plan - shares (in shares)		109,000
Restricted stock, net	0	18	(18)	0	0	0
Restricted stock, net - shares (in shares)		1,794,000
Reclassification of net gains on derivatives into earnings	493	0	0	0	0	493
Amortization of payments from settlement of forward interest rate swaps	376	0	0	0	0	376
Issuance of common stock from equity offering, net	163,771	160	163,611	0	0	0
Issuance of common stock from equity offering, net - shares (in shares)	16,046,512	16,047,000
Other	(346)	0	(8)	0	0	(338)
Balances at end of period at Dec. 31, 2009	1,086,582	1,232	1,882,377	(29,187)	(766,975)	(865)
Balances at end of period - shares (in shares) at Dec. 31, 2009		123,206,000
Compensation expense related to restricted stock grants	20,759	0	20,759	0	0	0
Net loss	(48,901)	0	0	0	(48,901)	0
Issuance of common stock under Associate Stock Purchase Plan	1,020	1	1,019	0	0	0
Issuance of common stock under Associate Stock Purchase Plan - shares (in shares)		63,000
Restricted stock, net	0	10	(10)	0	0	0
Restricted stock, net - shares (in shares)		1,048,000
Reclassification of net gains on derivatives into earnings	505	0	0	0	0	505
Amortization of payments from settlement of forward interest rate swaps	376	0	0	0	0	376
Other	(344)	0	(1)	0	0	(343)
Balances at end of period at Dec. 31, 2010	1,059,997	1,243	1,904,144	(29,187)	(815,876)	(327)
Balances at end of period - shares (in shares) at Dec. 31, 2010	124,316,545	124,317,000
Compensation expense related to restricted stock grants	19,856	0	19,856	0	0	0
Net loss	(68,175)	0	0	0	(68,175)	0
Common stock issued in connection with an acquisition	1,538	1	1,537	0	0	0
Common stock issued in connection with an acquisition (in shares)		97,000
Equity component of convertible notes, net	76,801	0	76,801	0	0	0
Purchase of bond hedge	(77,007)	0	(77,007)	0	0	0
Issuance of warrants	45,066	0	45,066	0	0	0
Issuance of common stock under Associate Stock Purchase Plan	1,258	0	1,258	0	0	0
Issuance of common stock under Associate Stock Purchase Plan - shares (in shares)		68,000
Restricted stock, net	0	10	(10)	0	0	0
Restricted stock, net - shares (in shares)		2,089,000
Unrealized loss on marketable securities - restricted	(998)	0	0	0	0	(998)
Reclassification of net gains on derivatives into earnings	134	0	0	0	0	134
Amortization of payments from settlement of forward interest rate swaps	376	0	0	0	0	376
Purchase of treasury stock	(17,613)	0	0	(17,613)	0	0
Purchase of treasury stock (in shares)	1,217,100	(1,217,000)
Other	(1,025)	0	(825)	0	0	(200)
Balances at end of period at Dec. 31, 2011	$ 1,040,208	$ 1,254	$ 1,970,820	$ (46,800)	$ (884,051)	$ (1,015)
Balances at end of period - shares (in shares) at Dec. 31, 2011	125,354,137	125,354,000