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ARO Trust (Tables)

3 Months Ended

Mar. 31, 2022

Investments, Debt and Equity Securities [Abstract]

Investments within the ARO Trust were as follows (in millions):


			March 31, 2022												December 31, 2021
			Amortized Cost Basis						Fair Value						Amortized Cost Basis						Fair Value
Money Market Funds			$	9.7					$	9.7					$	5.9					$	5.9
U.S. Equity Funds			52.6						114.4						52.7						121.4
International Equity Funds			31.7						40.5						31.7						43.2
Municipal Bond Funds			87.7						85.0						87.7						90.0
Total			$	181.7					$	249.6					$	178.0					$	260.5