Stock-Based Compensation Plans (Summary of Nonvested Stock Options) (Details) (USD $)	12 Months Ended
Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Awards
Nonvested at January 1, 2012	77,350
Granted	9,500
Vested	(23,100)
Forfeited	(4,250)
Nonvested at December 31, 2012	59,500	77,350
Weighted- Average Grant Date Fair Value
Nonvested at January 1, 2012	$ 9.2
Granted	$ 13.0	$ 12.3	$ 11.72
Vested	$ 9.7
Forfeited	$ 11.79
Nonvested at December 31, 2012	$ 9.67	$ 9.2

The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology.

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 123R

-Paragraph A240

-Subparagraph c(1)

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (d)(1)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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