Revenue (Tables) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 26, 2019	Sep. 27, 2018	Sep. 26, 2019	Sep. 27, 2018
Disaggregation of Revenue [Line Items]
Revenues	$ 1,919.9	$ 1,813.7	$ 5,903.8	$ 5,386.7
Boeing [Member]
Disaggregation of Revenue [Line Items]
Revenues	1,542.0	1,465.5	4,705.1	4,262.2
Airbus [Member]
Disaggregation of Revenue [Line Items]
Revenues	284.1	263.8	934.0	869.0
Other Customer [Member]
Disaggregation of Revenue [Line Items]
Revenues	93.8	84.4	264.7	255.5
UNITED STATES
Disaggregation of Revenue [Line Items]
Revenues	1,620.6	1,534.0	4,935.8	4,460.8
UNITED KINGDOM
Disaggregation of Revenue [Line Items]
Revenues	177.4	184.4	577.6	574.1
Other International [Member]
Disaggregation of Revenue [Line Items]
Revenues	121.9	95.3	390.4	351.8
Total International [Member]
Disaggregation of Revenue [Line Items]
Revenues	$ 299.3	$ 279.7	$ 968.0	$ 925.9