Employee Incentive Plans - Amounts Recognized in Consolidated Financial Statements (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2022	Mar. 31, 2021
Allocation
Total unit-based compensation expense	$ 6.6	$ 6.5
Amount of related income tax benefit recognized in net income	1.6	1.5
Unit-based compensation	2.0	2.5
Restricted units
Allocation
Unit-based compensation	2.0	2.5
Cost of unit-based compensation charged to operating expense
Allocation
Total unit-based compensation expense	1.6	1.7
Cost of unit-based compensation charged to general and administrative expense
Allocation
Total unit-based compensation expense	$ 5.0	$ 4.8

Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

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