Other Current Liabilities (Details) - USD ($) $ in Millions	Dec. 31, 2017	Dec. 31, 2016
Other Liabilities, Current [Abstract]
Warranty accruals on completed contracts	$ 321.3	$ 271.9
Contingencies related to completed contracts	214.9	370.1
Other taxes payable	204.4	143.5
Social security liability	145.0	66.3
Compensation accrual	123.5	27.5
Redeemable financial liability	69.7	33.7
Liabilities held for sale	13.7	0.0
Other accrued liabilities	595.4	504.6
Total other current liabilities	$ 1,687.9	$ 1,417.6