Guarantees And Other Contingencies [Line Items]

No definition available.

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- Definition

Annual contribution to be paid by counterparty to a renewable resources program.

+ References

No definition available.

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- Definition

The price per MWh of available capacity that must be paid, in connection with an unconditional purchase obligation that has not been recognized for financial reporting purposes.

+ References

No definition available.

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- Definition

Unrecorded Unconditional Purchase Obligation, Fixed Energy Charge Per Mwh, Off-Peak

+ References

No definition available.

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- Definition

Unrecorded Unconditional Purchase Obligation, Fixed Energy Charge Per Mwh, On-Peak

+ References

No definition available.

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- Definition

Maximum number of power units that may be acquired, in connection with an unconditional purchase obligation that has not been recognized for financial reporting purposes.

+ References

No definition available.

+ Details

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- Definition

The minimum number of units that must be purchased, in connection with unconditional purchase obligations that have not been recognized for financial reporting purposes.

+ References

No definition available.

+ Details

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- Definition

The current carrying amount of the liability for the freestanding or embedded guarantor's obligations under the guarantee or each group of similar guarantees.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 460
-SubTopic 10
-Section 50
-Paragraph 4
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=124440162&loc=d3e12069-110248

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- Definition

Maximum potential amount of future payments (undiscounted) the guarantor could be required to make under the guarantee or each group of similar guarantees before reduction for potential recoveries under recourse or collateralization provisions.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 460
-SubTopic 10
-Section 50
-Paragraph 4
-Subparagraph (b)(1)
-URI http://asc.fasb.org/extlink&oid=124440162&loc=d3e12069-110248

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- Definition

Describe the approximate term of the guarantee or each group of similar guarantees.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 460
-SubTopic 10
-Section 50
-Paragraph 4
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=124440162&loc=d3e12069-110248

+ Details

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- Definition

The equity interest of noncontrolling shareholders, partners or other equity holders in consolidated entity.

+ References

No definition available.

+ Details

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- Definition

Amount of fixed and determinable portion of unrecorded unconditional purchase obligation to be paid in fifth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 440
-SubTopic 10
-Section 50
-Paragraph 4
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=123406679&loc=d3e25336-109308

+ Details

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- Definition

Amount of fixed and determinable portion of unrecorded unconditional purchase obligation to be paid in next fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

+ Details

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- Definition

Amount of fixed and determinable portion of unrecorded unconditional purchase obligation to be paid in fourth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

+ Details

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- Definition

Amount of fixed and determinable portion of unrecorded unconditional purchase obligation to be paid in second fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

+ Details

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- Definition

Amount of fixed and determinable portion of unrecorded unconditional purchase obligation to be paid in third fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

+ Details

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- Definition

Amount of the unrecorded obligation to transfer funds in the future for fixed or minimum amounts or quantities of goods or services at fixed or minimum prices (for example, as in take-or-pay contracts or throughput contracts).

+ References

+ Details

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- Definition

Amount of fixed and determinable portion of unrecorded unconditional purchase obligation to be paid after fifth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 440
-SubTopic 10
-Section 50
-Paragraph 4
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=123406679&loc=d3e25336-109308

+ Details

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- Definition

The amount purchased during the period under an unrecorded unconditional purchase obligation (for example, under the take-or-pay or throughput contract).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 440
-SubTopic 10
-Section 50
-Paragraph 4
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=123406679&loc=d3e25336-109308

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Contingencies and Commitments (Guarantees) (Details) $ in Millions	12 Months Ended
	Dec. 31, 2021 USD ($) $ / MW $ / MWh MW	Dec. 31, 2020 USD ($)	Dec. 31, 2019 USD ($)
Guarantees And Other Contingencies [Line Items]
Total	$ 12,473
2022	2,317
2023	2,404
2024	1,174
2025	1,348
2026	642
Beyond 2026	4,588
Other
Guarantees And Other Contingencies [Line Items]
Total	4,445
2022	1,489
2023	1,657
2024	412
2025	639
2026	36
Beyond 2026	$ 212
Variable Interest Entity, Primary Beneficiary \| Aviator Wind Class B Membership
Guarantees And Other Contingencies [Line Items]
Ownership percentage	49.00%
Consumers Energy Company
Guarantees And Other Contingencies [Line Items]
Total	$ 11,978
2022	2,209
2023	2,343
2024	1,126
2025	1,303
2026	618
Beyond 2026	$ 4,379
Consumers Energy Company \| Palisades Power Purchase Agreement \| Financing Obligation
Guarantees And Other Contingencies [Line Items]
Annual average capacity (in MW) \| MW	798
Consumers Energy Company \| Total PPAs
Guarantees And Other Contingencies [Line Items]
Total	$ 8,028
2022	828
2023	747
2024	762
2025	709
2026	606
Beyond 2026	4,376
Consumers Energy Company \| Other
Guarantees And Other Contingencies [Line Items]
Total	3,950
2022	1,381
2023	1,596
2024	364
2025	594
2026	12
Beyond 2026	3
Consumers Energy Company \| MCV PPA
Guarantees And Other Contingencies [Line Items]
Total	2,204
2022	349
2023	348
2024	346
2025	306
2026	231
Beyond 2026	$ 624
PPA minimum quantity required \| MW	1,240
PPA fixed energy charge per MWh, on-peak (in dollars per MWh) \| $ / MWh	6.30
PPA fixed energy charge per MWh, off-peak (in dollars per MWh) \| $ / MWh	6.00
Annual contribution to renewable resources program by counterparty	$ 5
Purchases	$ 348	$ 298	$ 318
Consumers Energy Company \| MCV PPA \| Year End Through March 2025
Guarantees And Other Contingencies [Line Items]
PPA capacity charge per MWh (in dollars per MWh) \| $ / MW	10.14
Consumers Energy Company \| MCV PPA \| March 2025 Through Termination
Guarantees And Other Contingencies [Line Items]
PPA capacity charge per MWh (in dollars per MWh) \| $ / MW	5.00
Consumers Energy Company \| Palisades PPA
Guarantees And Other Contingencies [Line Items]
Total	$ 116
2022	116
2023	0
2024	0
2025	0
2026	0
Beyond 2026	0
Purchases	413	403	395
Consumers Energy Company \| Related-party PPAs
Guarantees And Other Contingencies [Line Items]
Total	342
2022	65
2023	65
2024	65
2025	47
2026	29
Beyond 2026	71
Consumers Energy Company \| Other PPAs
Guarantees And Other Contingencies [Line Items]
Total	5,366
2022	298
2023	334
2024	351
2025	356
2026	346
Beyond 2026	3,681
Purchases	$ 338	$ 327	$ 336
Guarantees
Guarantees And Other Contingencies [Line Items]
Expiration Date	indefinite
Maximum Obligation	$ 30
Carrying Amount	$ 0
Guarantees \| Consumers Energy Company
Guarantees And Other Contingencies [Line Items]
Expiration Date	indefinite
Maximum Obligation	$ 30
Carrying Amount	$ 0
Indemnification Agreement From Purchase Of Variable Interest Entity
Guarantees And Other Contingencies [Line Items]
Expiration Date	indefinite
Maximum Obligation	$ 314
Carrying Amount	$ 0
Indemnity Obligations From Stock And Asset Sales Agreements
Guarantees And Other Contingencies [Line Items]
Expiration Date	indefinite
Maximum Obligation	$ 225
Carrying Amount	4
Tax And Other Indemnity Obligations \| Consumers Energy Company
Guarantees And Other Contingencies [Line Items]
Carrying Amount	$ 1