Stock-Based Compensation (Details 2) (USD $)	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Summary of options outstanding
Exercise price range, lower range limit	$ 6.21	$ 6.21	$ 6.21
Exercise price range, upper range limit	$ 40.28	$ 40.28	$ 40.28
Number of Options Outstanding	152,896
Weighted Average Remaining Contractual Life	1 year 10 months 24 days	2 years 9 months 18 days	3 years 6 months
Weighted Average Exercise Price	$ 26.15
Number of Options Exercisable	152,896
Options Exercisable, Weighted Average Exercise Price	$ 26.15
Price Range One [Member]
Summary of options outstanding
Exercise price range, lower range limit	$ 6.21
Exercise price range, upper range limit	$ 8.00
Number of Options Outstanding	20,500
Weighted Average Remaining Contractual Life	2 years 10 months 24 days
Weighted Average Exercise Price	$ 6.21
Number of Options Exercisable	20,500
Options Exercisable, Weighted Average Exercise Price	$ 6.21
Price Range Two [Member]
Summary of options outstanding
Exercise price range, lower range limit	$ 16.01
Exercise price range, upper range limit	$ 20.00
Number of Options Outstanding	37,485
Weighted Average Remaining Contractual Life	1 year 10 months 24 days
Weighted Average Exercise Price	$ 17.74
Number of Options Exercisable	37,485
Options Exercisable, Weighted Average Exercise Price	$ 17.74
Price Range Three [Member]
Summary of options outstanding
Exercise price range, lower range limit	$ 24.01
Exercise price range, upper range limit	$ 28.00
Number of Options Outstanding	19,916
Weighted Average Remaining Contractual Life	9 months 18 days
Weighted Average Exercise Price	$ 26.61
Number of Options Exercisable	19,916
Options Exercisable, Weighted Average Exercise Price	$ 26.61
Price Range Four [Member]
Summary of options outstanding
Exercise price range, lower range limit	$ 32.01
Exercise price range, upper range limit	$ 36.00
Number of Options Outstanding	56,105
Weighted Average Remaining Contractual Life	2 years 3 months 18 days
Weighted Average Exercise Price	$ 34.75
Number of Options Exercisable	56,105
Options Exercisable, Weighted Average Exercise Price	$ 34.75
Price Range Five [Member]
Summary of options outstanding
Exercise price range, lower range limit	$ 36.01
Exercise price range, upper range limit	$ 40.00
Number of Options Outstanding	14,844
Weighted Average Remaining Contractual Life	10 months 24 days
Weighted Average Exercise Price	$ 37.94
Number of Options Exercisable	14,844
Options Exercisable, Weighted Average Exercise Price	$ 37.94
Price Range Six [Member]
Summary of options outstanding
Exercise price range, lower range limit	$ 40.01
Exercise price range, upper range limit	$ 44.00
Number of Options Outstanding	4,046
Weighted Average Remaining Contractual Life	1 year 9 months 18 days
Weighted Average Exercise Price	$ 40.28
Number of Options Exercisable	4,046
Options Exercisable, Weighted Average Exercise Price	$ 40.28