Annual report pursuant to Section 13 and 15(d)

Commitments and Contingencies - Additional Information (Details)

v2.4.1.9
Commitments and Contingencies - Additional Information (Details) (USD $)
In Thousands, unless otherwise specified
12 Months Ended
Dec. 31, 2014
Dec. 31, 2013
Dec. 31, 2012
Commitments And Contingencies [Line Items]      
Rent expense $ 750us-gaap_OperatingLeasesRentExpenseNet $ 910us-gaap_OperatingLeasesRentExpenseNet $ 806us-gaap_OperatingLeasesRentExpenseNet
Chief Executive Officer | Maximum      
Commitments And Contingencies [Line Items]      
Period of salary continuation upon termination 36 months    
Certain key employees | Maximum      
Commitments And Contingencies [Line Items]      
Period of salary continuation upon termination 24 months    
Offices and Certain Equipment      
Commitments And Contingencies [Line Items]      
Operating leases expiration date Dec. 31, 2019