Stock Based Compensation (Additional Information Regarding Stock Award Activity) (Details) (Stock Awards [Member], USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended				6 Months Ended
	Jun. 30, 2014		Jun. 30, 2013		Jun. 30, 2014		Jun. 30, 2013
Stock Awards [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted-Average Grant Date Fair Value of Shares Granted During the Period	$ 18.51		$ 19.47		$ 17.78		$ 19.47
Total Grant Date Fair Value of Shares Vested During the Period	$ 3,191		$ 3,839		$ 3,195		$ 3,839
Share-based Liability Awards Paid During the Period	$ 0	[1]	$ 103	[1]	$ 0	[1]	$ 103	[1]

[1] Amount reflects the issuance of performance share awards during the period.