Fair Value Measurements (Schedule of Carrying Values and Estimated Fair Values of Senior Notes) (Details) - Crestwood Midstream Partners LP - USD ($) $ in Millions	Mar. 31, 2022	Dec. 31, 2021
2025 Senior Notes
Debt Instrument [Line Items]
Carrying Amount	$ 496.8	$ 496.5
Fair Value	503.8	511.9
2027 Senior Notes
Debt Instrument [Line Items]
Carrying Amount	594.5	594.2
Fair Value	595.1	615.0
February 2029 Senior Notes
Debt Instrument [Line Items]
Carrying Amount	691.2	690.8
Fair Value	699.7	727.3
April 2029 Senior Notes
Debt Instrument [Line Items]
Carrying Amount	480.0	0.0
Fair Value	$ 480.3	$ 0.0