Supplemental Balance Sheet Information

12 Months Ended

Dec. 31, 2021

Organization Consolidation And Presentation Of Financial Statements [Abstract]

Supplemental Balance Sheet Information

2. Supplemental Balance Sheet Information

	As of December 31,
	2021			2020
	(In millions of dollars)
Trade Receivables, net
Billed trade receivables	$	333.5		$	113.6
Allowance for doubtful receivables		(0.8	)		(0.8	)
Trade receivables, net	$	332.7		$	112.8
Inventories
Finished products	$	90.3		$	37.2
Work-in-process		162.2			46.0
Raw materials		143.0			62.3
Operating supplies		9.1			6.5
Total	$	404.6		$	152.0
Property, Plant and Equipment, net
Land and improvements	$	26.0		$	21.5
Buildings and leasehold improvements		179.0			117.2
Machinery and equipment		1,151.5			847.4
Construction in progress1		75.3			37.8
Property, plant and equipment, gross		1,431.8			1,023.9
Accumulated depreciation and amortization		(480.4	)		(398.4	)
Assets held for sale		3.8			1.7
Property, plant and equipment, net	$	955.2		$	627.2
Other Accrued Liabilities
Uncleared cash disbursements	$	10.9		$	2.1
Accrued income taxes and other taxes payable		9.5			5.2
Accrued annual contribution to Salaried VEBA – Note 5		—			1.7
Accrued interest		9.9			11.6
Short-term environmental accrual – Note 10		2.6			3.7
Other – Note 3 and Note 8		25.5			17.1
Total	$	58.4		$	41.4
Long-Term Liabilities
Workers' compensation accruals	$	31.9		$	30.6
Long-term environmental accrual – Note 10		14.2			15.1
Other long-term liabilities		26.4			31.6
Total	$	72.5		$	77.3

¹ Based on market conditions, we temporarily idled projects within Construction in progress totaling $24.9 million and $20.0 million as of December 31, 2021 and December 31, 2020, respectively, all of which are expected to resume at a future date.