XML 47 R36.htm IDEA: XBRL DOCUMENT v3.8.0.1
Pension Plans - Components of Net Periodic Pension Cost (Detail) - USD ($)
$ in Thousands
3 Months Ended 9 Months Ended
Sep. 30, 2017
Sep. 30, 2016
Sep. 30, 2017
Sep. 30, 2016
Compensation And Retirement Disclosure [Abstract]        
Service cost $ 65 $ 42 $ 192 $ 152
Interest cost 363 370 1,092 1,099
Expected return on plan assets (476) (470) (1,427) (1,369)
Recognized net actuarial loss 80 146 324 392
Net periodic pension cost $ 32 $ 88 $ 181 $ 274