Income Taxes - Schedule of Components of Income Tax Expense (Detail) (USD $)
In Thousands, unless otherwise specified
12 Months Ended
Dec. 31, 2014
Dec. 31, 2013
Dec. 31, 2012
Income Tax Disclosure [Abstract]      
Current $ 2,607 $ 409 $ 71
Deferred 28 550 (240)
Expense of operating loss carryforwards 536 1,351 1,240
Change in valuation allowance (12)    
Income tax expense $ 3,159 $ 2,310 $ 1,071