Consolidated Stockholders' Equity Statements (Parenthetical) (USD $) In Millions, except Per Share data, unless otherwise specified	12 Months Ended
Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Adjustments to pension and postretirement liability, tax benefit	$ 3.2	$ 4.8	$ 1.0
Dividends declared per share	$ 0.20	$ 0.20	$ 0.20
Paid-In Capital [Member]
Dividends declared per share			$ 0.20
Retained Earnings [Member]
Dividends declared per share	$ 0.20	$ 0.20	$ 0.20
Accumulated Other Comprehensive Income (Loss), Pension and Postretirement Liability [Member]
Adjustments to pension and postretirement liability, tax benefit	$ 3.2	$ 4.8	$ 1.0
Dividends declared per share	$ 0.20

Tax effect, net of reclassification adjustments, of pension and other postretirement benefit plans (gain) loss included in accumulated other comprehensive income (loss).

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 220

-SubTopic 10

-Section 45

-Paragraph 12

-URI http://asc.fasb.org/extlink&oid=20435746&loc=d3e640-108580

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 220

-SubTopic 10

-Section 45

-Paragraph 10A

-Subparagraph (i-k)

-URI http://asc.fasb.org/extlink&oid=20435746&loc=SL7669646-108580

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration