Common Stock (Outstanding Performance Share Awards) (Details) - USD ($) $ / shares in Units, $ in Thousands		12 Months Ended
		Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Performance Shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Performance Shares Payout Level		100.00%
Share based compensation, outstanding at beginning of period, in shares	[1]	130,136
Shares awards, number of shares awarded in period		60,835
Performance shares awards, number of shares expired in period		(24,527)
Share based compensation, outstanding at end of period, in shares	[1]	166,444	130,136
Shares outstanding, weighted average grant date fair value,beginning of period	[1]	$ 32.72
Performance shares awards, Weighted Average Grant Date Fair Value		38.11	$ 35.72	$ 26.36
Performance shares expired, weighted average grant date fair value		34.69
Shares outstanding, weighted average grant date fair value, end of period	[1]	$ 34.40	$ 32.72
Unrecognized Compensation Expense at end of period	[1],[2]	$ 2,189
Aggregated intrinsic value for shares outstanding at end of period	[1]	$ 7,740
Unrecognized compensation expense, period for recognition		1 year
Restricted Stock with a Performance Condition [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares awards, number of shares awarded in period			27,624
Share-based Compensation Arrangement by Share-based Payment Award, Award Requisite Service Period			5 years

[1] On December 15, 2015, the Company issued a stock based retention grant to the Chief Executive Officer (CEO) of 27,624 shares in accordance with the Amended and Restated 2007 LTIP that is eligible for vesting based on the achievement of certain performance conditions and a five year service period, as stated in the CEO's employment agreement. The performance condition was met as of November 2016 as determined by the Compensation Committee, and has been included in the beginning and ending balance in the table above.

[2] The unrecognized compensation expense is expected to be recognized over the weighted average remaining contractual term of the awards of approximately one year, except for the CEO retention grant.