Leases - Minimum Annual Rental Commitments post Topic 842 (Details) $ in Millions	Jun. 30, 2019 USD ($)
Operating Leases
Remainder of 2019	$ 5
2020	11
2021	11
2022	5
2023	3
2024	2
2025 and thereafter	35
Total minimum lease payments	72
Less discount	21
Present value of minimum lease payments	51
Finance Leases
Remainder of 2019	14
2020	23
2021	22
2022	19
2023	18
2024	16
2025 and thereafter	90
Total minimum lease payments	202
Less discount	132
Present value of minimum lease payments	70
Consumers Energy Company
Operating Leases
Remainder of 2019	5
2020	9
2021	9
2022	4
2023	3
2024	2
2025 and thereafter	28
Total minimum lease payments	60
Less discount	17
Present value of minimum lease payments	43
Finance Leases
Remainder of 2019	14
2020	23
2021	22
2022	19
2023	18
2024	16
2025 and thereafter	90
Total minimum lease payments	202
Less discount	132
Present value of minimum lease payments	70
Pipelines and PPAs
Finance Leases
Remainder of 2019	9
2020	17
2021	17
2022	14
2023	13
2024	13
2025 and thereafter	79
Total minimum lease payments	162
Less discount	128
Present value of minimum lease payments	34
Pipelines and PPAs \| Consumers Energy Company
Finance Leases
Remainder of 2019	9
2020	17
2021	17
2022	14
2023	13
2024	13
2025 and thereafter	79
Total minimum lease payments	162
Less discount	128
Present value of minimum lease payments	34
Other
Finance Leases
Remainder of 2019	5
2020	6
2021	5
2022	5
2023	5
2024	3
2025 and thereafter	11
Total minimum lease payments	40
Less discount	4
Present value of minimum lease payments	36
Other \| Consumers Energy Company
Finance Leases
Remainder of 2019	5
2020	6
2021	5
2022	5
2023	5
2024	3
2025 and thereafter	11
Total minimum lease payments	40
Less discount	4
Present value of minimum lease payments	$ 36

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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