Warranties - Change in Carrying Value of Company's Warranty Liability (Detail) - USD ($) $ in Thousands |
9 Months Ended | |||
|---|---|---|---|---|
Sep. 30, 2016 |
Sep. 30, 2015 |
Jun. 30, 2016 |
Dec. 31, 2015 |
|
| Guarantees [Abstract] | ||||
| Product Warranty Accrual, Beginning Balance | $ 1,258 | $ 1,262 | ||
| Accrual | 267 | 344 | ||
| Warranty payments | (170) | $ (348) | ||
| Product Warranty Accrual, Ending balance | $ 1,355 | |||
| FOX | ||||
| Schedule of Equity Method Investments [Line Items] | ||||
| Non-controlling interest | 23.00% | 33.10% | 41.20% | |