Leases - Minimum Annual Rental Commitments post Topic 842 (Details) $ in Millions	Sep. 30, 2019 USD ($)
Operating Leases
Remainder of 2019	$ 2
2020	11
2021	11
2022	5
2023	3
2024	2
2025 and thereafter	35
Total minimum lease payments	69
Less discount	21
Present value of minimum lease payments	48
Finance Leases
Remainder of 2019	7
2020	23
2021	22
2022	19
2023	18
2024	16
2025 and thereafter	90
Total minimum lease payments	195
Less discount	126
Present value of minimum lease payments	69
Consumers Energy Company
Operating Leases
Remainder of 2019	2
2020	9
2021	9
2022	4
2023	3
2024	2
2025 and thereafter	29
Total minimum lease payments	58
Less discount	17
Present value of minimum lease payments	41
Finance Leases
Remainder of 2019	7
2020	23
2021	22
2022	19
2023	18
2024	16
2025 and thereafter	90
Total minimum lease payments	195
Less discount	126
Present value of minimum lease payments	69
Pipelines and PPAs
Finance Leases
Remainder of 2019	4
2020	17
2021	17
2022	14
2023	13
2024	13
2025 and thereafter	79
Total minimum lease payments	157
Less discount	123
Present value of minimum lease payments	34
Pipelines and PPAs \| Consumers Energy Company
Finance Leases
Remainder of 2019	4
2020	17
2021	17
2022	14
2023	13
2024	13
2025 and thereafter	79
Total minimum lease payments	157
Less discount	123
Present value of minimum lease payments	34
Other
Finance Leases
Remainder of 2019	3
2020	6
2021	5
2022	5
2023	5
2024	3
2025 and thereafter	11
Total minimum lease payments	38
Less discount	3
Present value of minimum lease payments	35
Other \| Consumers Energy Company
Finance Leases
Remainder of 2019	3
2020	6
2021	5
2022	5
2023	5
2024	3
2025 and thereafter	11
Total minimum lease payments	38
Less discount	3
Present value of minimum lease payments	$ 35

Finance Lease, Liability, Payments, Due After Year Six

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Present value of lessee's discounted obligation for lease payments from finance lease.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 50
-Paragraph 6
-URI http://asc.fasb.org/extlink&oid=77888426&loc=SL77918701-209980

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