XML 53 R39.htm IDEA: XBRL DOCUMENT v3.7.0.1
Investments - Summary of Securities Available for Sale (Detail) - USD ($)
$ in Thousands
3 Months Ended 6 Months Ended
Jun. 30, 2017
Jun. 30, 2016
Jun. 30, 2017
Jun. 30, 2016
Investments Debt And Equity Securities [Abstract]        
Proceeds from sales and maturities (fair value) $ 85,293 $ 112,786 $ 107,622 $ 165,152
Gross realized gains 1,813 $ 576 1,813 1,261
Gross realized losses $ (103)   $ (166) $ (18)