Balance Sheet Accounts

3 Months Ended

Mar. 31, 2022

Organization, Consolidation and Presentation of Financial Statements [Abstract]

Balance Sheet Accounts

Balance Sheet Accounts

a. Fair Value of Financial Instruments

Financial instruments are classified using a three-tiered fair value hierarchy, which prioritizes the inputs used in measuring fair value. These tiers include: Level 1, defined as observable inputs such as quoted prices in active markets; Level 2, defined as inputs other than quoted prices in active markets that are either directly or indirectly observable; and Level 3, defined as unobservable inputs in which little or no market data exists, therefore requiring an entity to develop its own assumptions.

			Fair value measurement as of March 31, 2022
	Total		Quoted Prices in Active Markets for Identical Assets (Level 1)		Other Observable Inputs (Level 2)		Unobservable Inputs (Level 3)
	(In millions)
Money market funds	$	360.5	$	360.5	$	—	$	—
Registered investment companies	1.2		1.2		—		—
Commercial paper	139.9		—		139.9		—
Equity securities	10.1		10.1		—		—
Total	$	511.7	$	371.8	$	139.9	$	—

			Fair value measurement as of December 31, 2021
	Total		Quoted Prices in Active Markets for Identical Assets (Level 1)		Other Observable Inputs (Level 2)		Unobservable Inputs (Level 3)
	(In millions)
Money market funds	$	388.6	$	388.6	$	—	$	—
Registered investment companies	1.3		1.3		—		—
Commercial paper	35.0		—		35.0		—
Equity securities	10.6		10.6		—		—
Total	$	435.5	$	400.5	$	35.0	$	—

As of March 31, 2022 and December 31, 2021, the total estimated fair value for commercial paper was classified as cash and cash equivalents as the remaining maturity at date of purchase was less than three months.

The carrying amounts of certain of the Company’s financial instruments, including cash and cash equivalents, restricted cash, accounts receivable, accounts payable, accrued compensation, and other accrued liabilities, approximate fair value because of their short maturities.

The following table summarizes the estimated fair value and principal amount for outstanding debt obligations excluding finance lease obligations:

	Fair Value				Principal Amount
	March 31, 2022		December 31, 2021		March 31, 2022		December 31, 2021
	(In millions)
Term loan	$	269.8	$	275.8	$	275.6	$	282.2
21/4% Notes	229.9		266.1		145.9		145.9
Total	$	499.7	$	541.9	$	421.5	$	428.1

The fair value of the 2¼% Notes was determined using broker quotes that are based on open markets for the Company's debt securities (Level 2 securities). The fair value of the term loan was estimated based on a third-party model used to derive a relative value price using comparable corporate loans within a similar industry, credit quality, and currency.

b. Accounts Receivable

	March 31, 2022		December 31, 2021
	(In millions)
Billed receivables under long-term contracts	$	143.2	$	60.3
Other trade receivables	0.2		0.3
Accounts receivable	$	143.4	$	60.6

c. Other Current Assets

	March 31, 2022		December 31, 2021
	(In millions)
Deferred costs recoverable from the U.S. government	$	40.4	$	37.4
Income tax receivable	—		13.8
Inventories	11.1		10.0
Prepaid expenses	15.5		15.3
Other	26.6		23.0
Other current assets	$	93.6	$	99.5

d. Property, Plant and Equipment, net

	March 31, 2022		December 31, 2021
	(In millions)
Land	$	71.1	$	71.1
Buildings and improvements	505.1		503.0
Machinery and equipment, including capitalized software	501.6		499.1
Construction-in-progress	48.8		50.0
	1,126.6		1,123.2
Less: accumulated depreciation	(713.3)		(702.1)
Property, plant and equipment, net	$	413.3	$	421.1

e. Other Noncurrent Assets

	March 31, 2022		December 31, 2021
	(In millions)
Real estate held for entitlement and leasing	$	103.8	$	103.7
Deferred costs recoverable from the U.S. government	62.2		62.1
Receivable from Northrop Grumman Corporation for environmental remediation costs	33.0		34.5
Other	37.3		43.0
Other noncurrent assets	$	236.3	$	243.3

f. Other Current Liabilities

	March 31, 2022		December 31, 2021
	(In millions)
Accrued compensation and employee benefits	$	103.5	$	122.0
Income taxes payable	42.7		—
Other	66.9		50.7
Other current liabilities	$	213.1	$	172.7

As of March 31, 2022, the income tax payable balance totaled $42.7 million. The increase in the income tax payable balance compared with an income tax receivable balance of $13.8 million as of December 31, 2021, is primarily the result of the elimination of the option for the Company to deduct Research and Development ("R&D") expenditures in the current period and requires the Company to capitalize such costs and amortize the costs over five years when incurred in the U.S.