Shareholders' Equity Rollforward (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended		9 Months Ended						9 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013		Sep. 30, 2012		Sep. 30, 2013 Preferred stock	Dec. 31, 2012 Preferred stock	Sep. 30, 2013 Common stock 2	Sep. 30, 2012 Common stock 2	Sep. 30, 2013 Paid-in capital 2	Sep. 30, 2012 Paid-in capital 2	Sep. 30, 2013 Retained earnings		Sep. 30, 2012 Retained earnings		Sep. 30, 2013 Deferred compensation obligation	Sep. 30, 2012 Deferred compensation obligation	Sep. 30, 2013 Accumulated other comprehensive loss 3		Sep. 30, 2012 Accumulated other comprehensive loss 3		Sep. 30, 2013 Treasury stock	Sep. 30, 2012 Treasury stock
Increase (Decrease) in Stockholders' Equity [Roll Forward]
As of beginning balance			$ 895,116		$ 846,309		$ 1,150	$ 1,150	$ 364	$ 270	$ 849,046	$ 690,131	$ 45,790		$ 157,242		$ 3,111	$ 3,620	$ (982)	[1]	$ (1,084)	[1]	$ (3,363)	$ (3,870)
Net loss	(98,900)	(32,611)	(140,721)		(50,148)								(140,721)		(50,148)
Dividends Declared			(5,175)	[2]
Dividends Declared					(5,176)	[3]									(5,176)	[3]
All Other Changes			46,563		4,297				101	1	46,404	4,228					(384)	(548)	56	[1]	69	[1]	386	547
As of ending balance	795,783	795,282	795,783		795,282		1,150	1,150	465	271	895,450	694,359	(100,106)		101,918		2,727	3,072	(926)	[1]	(1,015)	[1]	(2,977)	(3,323)
Preferred stock dividends	$ (1,725)	$ 0	$ (5,175)		$ 0								$ (5,175)	[2]

[1] The Accumulated other comprehensive loss (“AOCL”) is entirely attributable to our defined benefit pension and postretirement health care plans. The changes in the balance of AOCL for the nine months ended September 30, 2013 and 2012 represent reclassifications from AOCL to net periodic benefit expense, a component of General and administrative expenses, of $86 and $106 and are presented above net of taxes of $30 and $37.

[2] Includes dividends of $450.00 per share of 6% Convertible Perpetual Preferred Stock (the “6% Preferred Stock”).

[3] Includes dividends of $0.1125 per share of common stock.