Commitments and Contingencies Self Insurance (Details) - USD ($) $ in Millions	Mar. 31, 2020	Dec. 31, 2019
Crestwood Equity Partners LP
Other Commitments [Line Items]
Self Insurance Reserve	$ 9.7	$ 9.7
Self Insurance Reserve Expected To Be Paid Subsequent To Next Fiscal Year	6.2
Crestwood Midstream Partners LP
Other Commitments [Line Items]
Self Insurance Reserve	8.5	$ 8.3
Self Insurance Reserve Expected To Be Paid Subsequent To Next Fiscal Year	$ 5.2