XML 85 R65.htm IDEA: XBRL DOCUMENT v3.8.0.1
Income Taxes - Roll Forward of Liability for Unrecognized Tax Benefits Exclusive of Accrued Interest (Detail) - USD ($)
$ in Thousands
12 Months Ended
Dec. 31, 2017
Dec. 31, 2016
Dec. 31, 2015
Reconciliation of Unrecognized Tax Benefits      
Balance, beginning of period $ 4,050 $ 3,396 $ 3,325
Increase in previous year tax positions 123    
Decrease in previous year tax positions   0 (389)
Increase in current year tax positions 587 448 270
Decrease due to lapse of statute of limitations (773) 0 (14)
Increase related to adjustment of previous estimates of activity 256 206 204
Balance, end of period $ 4,243 $ 4,050 $ 3,396