Statement of Consolidated Stockholders' Equity (USD $) In Millions, except Share data, unless otherwise specified	Total		Common Stock	Additional Paid in Capital	Retained Earnings	Treasury Stock	Accumulated Other Comprehensive Loss
Beginning balance at Dec. 31, 2012	$ 1,070.8		$ 0.2	$ 1,017.7	$ 151.2	$ (72.3)	$ (26.0)
Beginning balance, shares at Dec. 31, 2012	19,313,235		19,313,235
Stockholders' Equity [Roll Forward]
Net income	77.5				77.5
Other comprehensive income, net of tax	3.1						3.1
Issuance of non-vested shares to employees, shares			76,336
Issuance of common shares to non-employee directors, shares			2,916
Issuance of common shares to non-employee directors	0.2			0.2
Issuance of common shares to employees upon vesting of restricted stock units and performance shares, shares			36,503
Cancellation of employee non-vested shares			(820)
Cancellation of shares to cover employees’ tax withholdings upon vesting of non-vested shares, shares			(40,075)
Cancellation of shares to cover employees’ tax withholdings upon vesting of non-vested shares	(2.4)			(2.4)
Repurchase of common stock, shares	(707,077)		(707,077)
Repurchase of common stock	(43.9)					(43.9)
Distribution from bankruptcy trust, shares			(9,001)
Distribution from bankruptcy trust, dividends					0.6
Distribution of bankruptcy trust, share value	0.6	[1]				(0.6)
Cash dividends on common stock ($0.90 per share)	(17.3)				(17.3)
Excess tax benefit upon vesting of non-vested shares and dividend payment on unvested shares expected to vest	1.0			1.0
Amortization of unearned equity compensation	5.9			5.9
Dividends on unvested equity awards that were canceled	0.2				0.2
Ending balance at Sep. 30, 2013	$ 1,095.1		$ 0.2	$ 1,022.4	$ 212.2	$ (116.8)	$ (22.9)
Ending balance, shares at Sep. 30, 2013	18,672,017		18,672,017

[1] See Note 11 for discussion of the distribution.