Stock-Based Compensation (Details) (USD $) In Millions, except Share data, unless otherwise specified	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding [Roll Forward]
Number of Shares, Options outstanding, Beginning of period (in shares)	233,985
Number of Shares, Granted (in shares)	0
Number of Shares, Exercised (in shares)	(152,783)
Number of Shares, Cancelled (in shares)	0
Number of Shares, Options outstanding, End of period (in shares)	81,202	233,985
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price [Roll Forward]
Weighted Average Exercise Price, Beginning of period (in dollars per share)	$ 16.78
Weighted Average Exercise Price, Granted (in dollars per share)	$ 0.00
Weighted Average Exercise Price, Exercised (in dollars per share)	$ 16.23
Weighted Average Exercise Price, Cancelled (in dollars per share)	$ 0.00
Weighted Average Exercise Price, End of period (in dollars per share)	$ 17.80	$ 16.78
Share-based Compensation Arrangement by Share-based Payment Award, Options, Additional Disclosures [Abstract]
Weighted Average Remaining Contractual Terms, Options outstanding (in years)	3 years 3 months 10 days
Aggregate Intrinsic Value, Options outstanding	$ 3.0
Number of Shares, Options exercisable (in shares)	81,202	233,985
Weighted Average Exercise Price, Options exercisable (in dollars per share)	$ 17.80	$ 16.78
Weighted Average Remaining Contractual Terms, Options exercisable (in years)	3 years 3 months 10 days	4 years 1 month 5 days
Aggregate Instrinsic Value, Options exercisable	$ 3.0	$ 4.5