Consolidated Balance Sheets (Unaudited) - USD ($) $ in Millions	Mar. 31, 2020	Dec. 31, 2019
Current assets:
Cash and cash equivalents	$ 307.2	$ 264.3
Short-term investments	39.3	78.7
Receivables:
Trade receivables, net	175.2	167.1
Other	22.6	18.1
Contract assets	47.1	54.6
Inventories	194.6	177.6
Prepaid expenses and other current assets	20.4	19.4
Total current assets	806.4	779.8
Property, plant and equipment, net	630.9	622.0
Operating lease assets	28.8	25.8
Deferred tax assets, net	2.0	11.8
Intangible assets, net	28.9	29.6
Goodwill	18.8	18.8
Other assets	37.3	38.4
Total	1,553.1	1,526.2
Current liabilities:
Accounts payable	113.9	92.0
Accrued salaries, wages and related expenses	28.3	34.4
Other accrued liabilities	56.9	44.0
Total current liabilities	199.1	170.4
Long-term portion of operating lease liabilities	27.8	25.2
Net liabilities of Salaried VEBA	32.5	32.6
Deferred tax liabilities	4.5	4.5
Long-term liabilities	75.3	67.0
Long-term debt	492.8	492.6
Total liabilities	832.0	792.3
Commitments and contingencies
Stockholders' equity:
Preferred stock, 5,000,000 shares authorized at both March 31, 2020 and December 31, 2019; no shares were issued and outstanding at March 31, 2020 and December 31, 2019	0.0	0.0
Common stock, par value $0.01, 90,000,000 shares authorized at both March 31, 2020 and at December 31, 2019; 22,624,880 shares issued and 15,789,594 shares outstanding at March 31, 2020; 22,550,827 shares issued and 15,868,304 shares outstanding at December 31, 2019	0.2	0.2
Additional paid in capital	1,060.3	1,062.9
Retained earnings	190.6	172.8
Treasury stock, at cost, 6,835,286 shares at March 31, 2020 and 6,682,523 shares at December 31, 2019, respectively	(475.9)	(463.4)
Accumulated other comprehensive loss	(54.1)	(38.6)
Total stockholders' equity	721.1	733.9
Total	$ 1,553.1	$ 1,526.2