v3.3.0.814
Income taxes (Details) - USD ($)
$ in Thousands
3 Months Ended 9 Months Ended
Sep. 30, 2015
Sep. 30, 2014
Sep. 30, 2015
Sep. 30, 2014
Dec. 31, 2014
Income taxes          
Income tax expense $ 115 $ 75 $ 401 $ 378  
Effective tax rate (as a percent) 2.40% 2.20% 2.20% 3.10%  
Deferred tax liabilities $ 2,930   $ 2,930    
Uncertain tax positions 359   359   $ 459
Uncertain tax positions, reduction to deferred tax assets 84   84   106
Accrued interest, net of federal income tax benefits, and penalties 46   46   $ 67
Unrecognized tax benefits that would affect the effective tax rate 229   229    
Reconciliation of unrecognized tax benefits          
Beginning balance, January 1, 2015     392    
Effective settlement during the current period     (79)    
Balance, September 30, 2015 $ 313   $ 313