Basis of Presentation - Additional Information (Detail) - AWE Management Limited |
3 Months Ended | 6 Months Ended | |||
|---|---|---|---|---|---|
Jun. 25, 2017 |
Jun. 26, 2016 |
Jun. 25, 2017 |
Jun. 26, 2016 |
Aug. 24, 2016 |
|
| Basis of Presentation [Line Items] | |||||
| Ownership interest percentage owned immediately before acquisition | 33.00% | ||||
| Ownership interest percentage owned including subsequent acquisition | 51.00% | ||||
| Net Sales | Segment Concentration Risk | Space Systems | |||||
| Basis of Presentation [Line Items] | |||||
| Concentration percentage | 100.00% | 100.00% | |||
| Net Sales | Equity Method Investment Risk | Space Systems | |||||
| Basis of Presentation [Line Items] | |||||
| Concentration percentage | 0.00% | 0.00% | |||
| Operating profit | Segment Concentration Risk | Space Systems | |||||
| Basis of Presentation [Line Items] | |||||
| Concentration percentage | 51.00% | 51.00% | |||
| Net Earnings | Equity Method Investment Risk | Space Systems | |||||
| Basis of Presentation [Line Items] | |||||
| Concentration percentage | 33.00% | 33.00% | |||