Acquisitions - Schedule of Revenues and Earnings Included in the Unaudited Consolidated Statements of Operations (Detail) - USD ($) $ in Millions |
3 Months Ended | 12 Months Ended | |||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|
Dec. 31, 2016 |
Oct. 02, 2016 |
Jul. 03, 2016 |
Apr. 03, 2016 |
Dec. 31, 2015 |
Sep. 27, 2015 |
Jun. 28, 2015 |
Mar. 29, 2015 |
Dec. 31, 2016 |
Dec. 31, 2015 |
Dec. 31, 2014 |
|
| Business Acquisition Pro Forma Information Nonrecurring Adjustment [Line Items] | |||||||||||
| Revenues: Net sales | $ 646.6 | $ 676.2 | $ 728.4 | $ 739.5 | $ 735.3 | $ 746.6 | $ 800.2 | $ 765.2 | $ 2,790.7 | $ 3,047.3 | $ 2,717.0 |
| Earnings: Income (loss) before tax | 135.3 | 173.9 | 54.2 | ||||||||
| ASP Grede Intermediate Holdings LLC [Member] | |||||||||||
| Business Acquisition Pro Forma Information Nonrecurring Adjustment [Line Items] | |||||||||||
| Revenues: Net sales | 787.3 | 906.8 | 572.1 | ||||||||
| Earnings: Income (loss) before tax | $ 17.9 | $ 43.3 | $ (19.2) | ||||||||