Consolidated Balance Sheets (Unaudited) - USD ($) $ in Millions	Jun. 27, 2019	Dec. 31, 2018
Assets
Cash and cash equivalents	$ 1,301.4	$ 773.6
Restricted Cash, Current	0.3	0.3
Accounts receivable, net	595.5	545.1
Unbilled Receivables, Current	613.9	469.4
Inventory, net	970.7	1,012.6
Other current assets	62.1	48.3
Total current assets	3,543.9	2,849.3
Property, plant and equipment, net	2,161.8	2,167.6
Operating Lease, Right-of-Use Asset	50.4	0.0
Unbilled Receivable, Non Current	10.7	54.1
Pension assets	324.8	326.7
Other assets	253.5	288.2
Total assets	6,345.1	5,685.9
Liabilities
Accounts payable	1,116.4	902.6
Accrued expenses	316.1	313.1
Profit sharing	37.9	68.3
Current portion of long-term debt	33.3	31.4
Operating Lease, Liability, Current	5.6	0.0
Advance payments, short-term	19.8	2.2
Billings in Excess of Cost, Current	160.7	157.9
Provision for Loss on Contracts	21.9	12.4
Deferred revenue and other deferred credits, short-term	20.0	20.0
Deferred grant income liability - current	7.7	16.0
Other current liabilities	70.7	58.2
Total current liabilities	1,810.1	1,582.1
Liabilities Noncurrent
Long-term debt	2,113.3	1,864.0
Operating Lease, Liability, Noncurrent	44.8	0.0
Advance payments, long-term	212.1	231.9
Pension/OPEB obligation	33.2	34.6
Billings in Excess of Cost, Noncurrent	361.4	369.8
Provision for Loss on Contacts, Non Current	135.8	170.6
Deferred grant income liability - non-current	28.9	28.0
Deferred revenue and other deferred credits	39.0	31.2
Other liabilities	97.8	135.6
Stockholders' Equity Attributable to Parent [Abstract]
Preferred stock, par value $0.01, 10,000,000 shares authorized, no shares issued	0.0	0.0
Additional Paid in Capital [Abstract]
Additional paid-in capital	1,105.5	1,100.9
AccumulatedOtherComprehensiveIncomeLossNetOfTaxAbstract
Accumulated other comprehensive loss	(209.6)	(196.6)
Retained Earnings Accumulated Deficit [Abstract]
Retained earnings	3,027.3	2,713.2
Treasury Stock, Value	(2,456.0)	(2,381.0)
Total stockholders’ equity	1,468.2	1,237.6
Noncontrolling interest	0.5	0.5
Total equity	1,468.7	1,238.1
Total liabilities and equity	6,345.1	5,685.9
Class A [Member]
Stockholders' Equity Attributable to Parent [Abstract]
Common stock	$ 1.0	$ 1.1