Fair Value (Tables)

12 Months Ended

Dec. 31, 2021

Schedule of Fair Value, Assets and Liabilities Measured on Recurring Basis

The following tables present financial assets and liabilities measured and recorded at fair value on our Consolidated Balance Sheets on a recurring basis and their level within the fair value hierarchy as of December 31, 2021 and December 31, 2020:


Recurring Fair Value Measurements December 31, 2021 (in millions)	Quoted Prices in Active Markets for Identical Assets (Level 1)		Significant Other Observable Inputs (Level 2)		Significant Unobservable Inputs (Level 3)		Balance as of December 31, 2021
Assets


Risk management assets	$	—	$	24.4	$	—	$	24.4

Available-for-sale debt securities	—		171.8		—		171.8
Total	$	—	$	196.2	$	—	$	196.2
Liabilities


Risk management liabilities	$	—	$	144.2	$	—	$	144.2

Total	$	—	$	144.2	$	—	$	144.2


Recurring Fair Value Measurements December 31, 2020 (in millions)	Quoted Prices in Active Markets for Identical Assets (Level 1)		Significant Other Observable Inputs (Level 2)		Significant Unobservable Inputs (Level 3)		Balance as of December 31, 2020
Assets


Risk management assets	$	—	$	13.2	$	—	$	13.2


Available-for-sale debt securities	—		170.9		—		170.9
Total	$	—	$	184.1	$	—	$	184.1
Liabilities

Risk management liabilities	$	—	$	222.8	$	—	$	222.8

Total	$	—	$	222.8	$	—	$	222.8

Debt Securities, Available-for-sale

The amortized cost, gross unrealized gains and losses, allowance for credit losses, and fair value of available-for-sale securities at December 31, 2021 and 2020 were:


December 31, 2021 (in millions)	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses(1)		Allowance for Credit Losses		Fair Value
Available-for-sale debt securities
U.S. Treasury debt securities	$	52.8	$	0.1	$	(0.4)	$	—	$	52.5
Corporate/Other debt securities	116.5		3.7		(0.7)		(0.2)		119.3
Total	$	169.3	$	3.8	$	(1.1)	$	(0.2)	$	171.8

December 31, 2020 (in millions)	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses(2)		Allowance for Credit Losses		Fair Value
Available-for-sale debt securities
U.S. Treasury debt securities	$	33.7	$	0.3	$	—	$	—	$	34.0
Corporate/Other debt securities	130.2		7.7		(0.5)		(0.5)		136.9
Total	$	163.9	$	8.0	$	(0.5)	$	(0.5)	$	170.9

(1) Fair value of U.S. Treasury debt securities and Corporate/Other debt securities in an unrealized loss position without an allowance for credit losses is $36.2 and $35.4 million, respectively, at December 31, 2021.

(2) Fair value of U.S. Treasury debt securities and Corporate/Other debt securities in an unrealized loss position without an allowance for credit losses is zero and $13.2 million, respectively, at December 31, 2020.

Carrying Amount And Estimated Fair Values Of Financial Instruments

The carrying amount and estimated fair values of these financial instruments were as follows:


At December 31, (in millions)	Carrying Amount 2021		Estimated Fair Value 2021		Carrying Amount 2020		Estimated Fair Value 2020
Long-term debt (including current portion)	$	9,241.5	$	10,415.7	$	9,243.1	$	11,034.2