Common Stock (Schedule of Restricted Stock Tax Expense and Deferred Tax) (Details) - USD ($) $ in Thousands		12 Months Ended
		Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Capitalized costs related to restricted stock award expense		$ 300	$ 300	$ 300
Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expense	[1]	2,594	2,755	3,471
Deferred tax benefit		908	964	1,215
Current tax benefit recognized		$ 183	$ 43	$ 39

[1] Any capitalized costs related to these expenses is less than $0.3 million for all years.