Consolidated Balance Sheets - USD ($) $ in Millions	Dec. 31, 2017	Dec. 31, 2016
Current Assets
Cash and cash equivalents	$ 535.0	$ 410.3
Marketable securities	20.0	0.0
Accounts receivable	215.5	136.4
Inventories	136.4	185.1
Other current assets, net	109.8	122.9
Total Current Assets	1,016.7	854.7
Noncurrent Assets
Property, plant and equipment, net	359.0	366.0
Recoverable from the U.S. government and other third parties for environmental remediation costs	231.1	239.8
Deferred income taxes	145.8	292.5
Goodwill	161.3	158.1
Intangible assets	85.5	94.4
Other noncurrent assets, net	259.3	244.0
Total Noncurrent Assets	1,242.0	1,394.8
Total Assets	2,258.7	2,249.5
Current Liabilities
Current portion of long-term debt	25.0	55.6
Accounts payable	100.9	96.2
Reserves for environmental remediation costs	35.2	37.1
Advance payments on contracts	237.8	221.8
Other current liabilities	195.9	173.0
Total Current Liabilities	594.8	583.7
Noncurrent Liabilities
Long-term debt	591.4	608.0
Reserves for environmental remediation costs	306.2	312.6
Pension benefits	492.8	548.2
Other noncurrent liabilities	171.1	161.4
Total Noncurrent Liabilities	1,561.5	1,630.2
Total Liabilities	2,156.3	2,213.9
Commitments and contingencies (Note 8)
Redeemable common stock, par value of $0.10; none issued and outstanding December 31, 2017; 0.1 million shares issued and outstanding as of December 31, 2016	0.0	1.1
Stockholders’ Equity
Preference stock, par value of $1.00; 15.0 million shares authorized; none issued or outstanding	0.0	0.0
Common stock, par value of $0.10; 150.0 million shares authorized; 73.6 million shares issued and outstanding as of December 31, 2017; 69.2 million shares issued and outstanding as of December 31, 2016	7.4	6.9
Other capital	503.1	456.9
Treasury stock at cost, 3.5 million shares as of December 31, 2017 and 2016	(64.5)	(64.5)
Accumulated deficit	(71.0)	(61.8)
Accumulated other comprehensive loss, net of income taxes	(272.6)	(303.0)
Total Stockholders’ Equity	102.4	34.5
Total liabilities, redeemable common stock, and stockholders’ (deficit) equity	$ 2,258.7	$ 2,249.5