Share-Based Compensation Plan Restricted stock service awards and performance awarded under the 2006 Equity Compensation Plan (Details) (2006 Equity Compensation Plan [Member], USD $) In Thousands, except Share data, unless otherwise specified	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Performance Shares [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward]
Non-vested at beginning of year (in shares)	0	10,511	21,702
Granted (in shares)	0	0	0
Vested (in shares)	0	(10,511)	(8,383)
Forfeited (in shares)	0	0	(2,808)
Non-vested at end of period (in shares)	0	0	10,511
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value [Abstract]
Non-vested at beginning of year (in dollars per share)	$ 0.00	$ 13.92	$ 14.27
Granted (in dollars per share)	$ 0.00	$ 0.00	$ 0.00
Vested (in dollars per share)	$ 0.00	$ 13.92	$ 14.59
Forfeited (in dollars per share)	$ 0.00	$ 0.00	$ 14.59
Non-vested at end of period (in dollars per share)	$ 0.00	$ 0.00	$ 13.92
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Aggregate Intrinsic Value [Abstract]
Non-vested at end of period	$ 0	$ 0	$ 186
Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward]
Non-vested at beginning of year (in shares)	119,250	109,944	64,518
Granted (in shares)	41,533	32,500	49,975
Vested (in shares)	(15,425)	(10,944)	(4,549)
Forfeited (in shares)	(11,250)	(12,250)	0
Non-vested at end of period (in shares)	134,108	119,250	109,944
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value [Abstract]
Non-vested at beginning of year (in dollars per share)	$ 16.39	$ 15.83	$ 14.96
Granted (in dollars per share)	$ 17.65	$ 17.96	$ 16.86
Vested (in dollars per share)	$ 15.59	$ 15.54	$ 14.79
Forfeited (in dollars per share)	$ 16.05	$ 16.33	$ 0.00
Non-vested at end of period (in dollars per share)	$ 16.66	$ 16.39	$ 15.83
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Aggregate Intrinsic Value [Abstract]
Non-vested at end of period	$ 2,415	$ 2,151	$ 1,942