Share-Based Compensation Arrangements (Nonvested Performance Shares) (Details) (Amended and Restated Two Thousand Three Stock Incentive Plan [Member], Performance Based Nonvested Shares [Member], USD $)	9 Months Ended
	Sep. 30, 2013
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Grant Date Fair Value	$ 26.05
Equity Instruments Other than Options Minimum Shares Earned	0
Equity Instruments Other than Options Maximum Shares Earned	60,300
Award Vesting Period	3 years
Equity Instruments Other than Options Shares Vesting Percentage	150.00%
Equity Instruments Other than Options Granted	45,225
Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Equity Instruments Other than Options Shares Earned to Target Percentage Minimum	0.00%
Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Equity Instruments Other than Options Shares Earned to Target Percentage Maximum	200.00%