Annual report pursuant to Section 13 and 15(d)

Accrued Liabilities (Reconciliation of Product Warranties) (Details)

v3.6.0.2
Accrued Liabilities (Reconciliation of Product Warranties) (Details) - USD ($)
$ in Thousands
12 Months Ended
Dec. 31, 2016
Dec. 31, 2015
Dec. 31, 2014
Accrued Liabilities, Current [Abstract]      
Balance at beginning of period $ 11,487 $ 11,148 $ 10,768
Provision for warranty claims 3,802 4,560 4,675
Warranty claims (3,726) (3,708) (3,906)
Other (108) (513) (389)
Balance at end of period $ 11,455 $ 11,487 $ 11,148