v3.7.0.1

Commitments and Contingencies - Additional Information (Detail) - $ / shares |  | 12 Months Ended |
--- | --- | --- | ---
Nov. 03, 2016 | Dec. 31, 2016 | Dec. 31, 2015
Registration Payment Arrangement [Line Items] |  |  |
Common stock, par value | $ 0.001 | $ 0.001 | $ 0.001
American Axle [Member] |  |  |
Registration Payment Arrangement [Line Items] |  |  |
Business acquisition date of acquisition agreement |  | Nov. 03, 2016 |
Common stock, par value | 0.01 |  |
Business acquisition cash consideration per share | $ 13.50 |  |
Business acquisition common stock conversation ratio | 50.00% |  |

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