Stock- Based Compensation (Details) (USD $)	12 Months Ended			1 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011	May 31, 2013 Deferred Stock Units [Member]	Dec. 31, 2013 Deferred Stock Units [Member]
Stock-Based Compensation [Abstract]
Shares available for future grant under the plan	891,219
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share Based Compensation Arrangement By Share Based Payment Award Non Option Equity Instruments Granted Per Director (in shares)				243
Expense recognized in connection with the issuance of Deferred Stock Units (in US dollars)	$ 394,000	$ 300,000	$ 300,000	$ 394,000
Expense per grant recognized in connection with the issuance of Deferred Stock Units (in US dollars)				$ 56,250
Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Outstanding Number					3,521