Summary of Significant Accounting Policies - Revenue Recognition (Details) - USD ($) $ / shares in Units, $ in Millions	1 Months Ended		3 Months Ended								12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Nov. 30, 2015	Aug. 31, 2015	May 31, 2015	Feb. 28, 2015	Dec. 31, 2016	Nov. 30, 2015	Nov. 30, 2014
Change in Accounting Estimate [Line Items]
Favorable effect of the changes in contract estimates on income (loss) from continuing operations before income taxes	$ 7.0		$ 18.0	$ (11.0)	$ 5.9	$ 5.2	$ 7.6	$ (38.5)	$ 17.3	$ (3.5)	$ 18.1	$ (17.1)	$ (49.3)
Favorable effect of the changes in contract estimates on net income (loss)	$ 7.0	$ (6.2)	$ 18.1	$ (11.1)	$ 5.9	$ 5.1	$ 7.7	$ (37.9)	$ 17.3	$ (3.3)	$ 18.0	$ (16.2)	$ (50.0)
Favorable effect of the changes in contract estimates on basic net (loss) income per share (in USD per share)	$ 0.11	$ (0.11)	$ 0.26	$ (0.17)	$ 0.09	$ 0.08	$ 0.12	$ (0.61)	$ 0.28	$ (0.06)	$ 0.27	$ (0.27)	$ (0.86)
Favorable effect of the changes in contract estimates on diluted net (loss) income per share (in USD per share)	$ 0.10	$ (0.11)	$ 0.25	$ (0.17)	$ 0.09	$ 0.08	$ 0.12	$ (0.61)	$ 0.25	$ (0.06)	$ 0.27	$ (0.27)	$ (0.86)
Aerospace and Defense | Contracts Accounted for under Percentage-of-Completion [Member]
Change in Accounting Estimate [Line Items]
Percentage of Net Sales											94.00%
Favorable effect of the changes in contract estimates on income (loss) from continuing operations before income taxes	$ 11.7										$ 14.1	$ 41.2	$ 9.2
Favorable effect of the changes in contract estimates on net income (loss)	$ 7.0										$ 8.5	$ 24.7	$ 5.5
Favorable effect of the changes in contract estimates on basic net (loss) income per share (in USD per share)	$ 0.11										$ 0.13	$ 0.40	$ 0.10
Favorable effect of the changes in contract estimates on diluted net (loss) income per share (in USD per share)	$ 0.09										$ 0.11	$ 0.40	$ 0.10