Fair Value Measurements - Assets and Liabilities (Details) - USD ($) $ in Millions	Mar. 31, 2022	Dec. 31, 2021
Assets:
Gross derivative assets	$ 1,453.8	$ 773.6
Liabilities:
Gross derivative liabilities	1,406.8	748.5
Fair value measured on recurring basis
Assets:
Total assets at fair value	1,468.5	788.3
Liabilities:
Total liabilities at fair value	1,406.8	748.5
Fair value measured on recurring basis | Level 1 Inputs
Assets:
Total assets at fair value	873.0	513.3
Liabilities:
Total liabilities at fair value	598.5	361.5
Fair value measured on recurring basis | Level 2 Inputs
Assets:
Total assets at fair value	587.4	272.3
Liabilities:
Total liabilities at fair value	802.5	383.2
Fair value measured on recurring basis | Level 3 Inputs
Assets:
Total assets at fair value	8.1	2.6
Liabilities:
Total liabilities at fair value	5.8	3.8
Commodity contracts | Fair value measured on recurring basis
Assets:
Gross derivative assets	1,429.0	763.5
Liabilities:
Gross derivative liabilities	1,395.0	743.9
Commodity contracts | Fair value measured on recurring basis | Level 1 Inputs
Assets:
Gross derivative assets	873.0	513.3
Liabilities:
Gross derivative liabilities	598.5	361.5
Commodity contracts | Fair value measured on recurring basis | Level 2 Inputs
Assets:
Gross derivative assets	547.9	247.6
Liabilities:
Gross derivative liabilities	790.7	378.6
Commodity contracts | Fair value measured on recurring basis | Level 3 Inputs
Assets:
Gross derivative assets	8.1	2.6
Liabilities:
Gross derivative liabilities	5.8	3.8
Interest rate contracts | Fair value measured on recurring basis
Assets:
Gross derivative assets	17.0	5.4
Liabilities:
Gross derivative liabilities		0.3
Interest rate contracts | Fair value measured on recurring basis | Level 1 Inputs
Assets:
Gross derivative assets	0.0	0.0
Liabilities:
Gross derivative liabilities		0.0
Interest rate contracts | Fair value measured on recurring basis | Level 2 Inputs
Assets:
Gross derivative assets	17.0	5.4
Liabilities:
Gross derivative liabilities		0.3
Interest rate contracts | Fair value measured on recurring basis | Level 3 Inputs
Assets:
Gross derivative assets	0.0	0.0
Liabilities:
Gross derivative liabilities		0.0
Foreign currency contracts | Fair value measured on recurring basis
Assets:
Gross derivative assets	7.7	4.7
Liabilities:
Gross derivative liabilities	11.8	4.3
Foreign currency contracts | Fair value measured on recurring basis | Level 1 Inputs
Assets:
Gross derivative assets	0.0	0.0
Liabilities:
Gross derivative liabilities	0.0	0.0
Foreign currency contracts | Fair value measured on recurring basis | Level 2 Inputs
Assets:
Gross derivative assets	7.7	4.7
Liabilities:
Gross derivative liabilities	11.8	4.3
Foreign currency contracts | Fair value measured on recurring basis | Level 3 Inputs
Assets:
Gross derivative assets	0.0	0.0
Liabilities:
Gross derivative liabilities	0.0	0.0
Cash surrender value of life insurance | Fair value measured on recurring basis
Assets:
Cash surrender value of life insurance	14.8	14.6
Cash surrender value of life insurance | Fair value measured on recurring basis | Level 1 Inputs
Assets:
Cash surrender value of life insurance	0.0	0.0
Cash surrender value of life insurance | Fair value measured on recurring basis | Level 2 Inputs
Assets:
Cash surrender value of life insurance	14.8	14.6
Cash surrender value of life insurance | Fair value measured on recurring basis | Level 3 Inputs
Assets:
Cash surrender value of life insurance	$ 0.0	$ 0.0