Guarantees And Other Contingencies [Line Items]

No definition available.

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- Definition

Describes the term of the unconditional purchase obligations that are not recorded as a liability on the balance sheet.

+ References

No definition available.

+ Details

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- Definition

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

+ References

No definition available.

+ Details

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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.

+ Details

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- Definition

Specifies length of time the contract can be extended at the end of the contract term.

+ References

No definition available.

+ Details

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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=118943654&loc=d3e12069-110248

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- 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=118943654&loc=d3e12069-110248

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- 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=118943654&loc=d3e12069-110248

+ Details

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- Definition

Amount of the fixed and determinable portion of the unrecorded unconditional purchase obligation maturing in the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 440
-SubTopic 10
-Section 50
-Paragraph 4
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=77896938&loc=d3e25336-109308

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount of the fixed and determinable portion of the unrecorded unconditional purchase obligation maturing in the next fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount of the fixed and determinable portion of the unrecorded unconditional purchase obligation maturing in the fourth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

+ Details

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Period Type:	instant

- Definition

Amount of the fixed and determinable portion of the unrecorded unconditional purchase obligation maturing in the second fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

+ Details

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Balance Type:	credit
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- Definition

Amount of the fixed and determinable portion of the unrecorded unconditional purchase obligation maturing in the third fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

+ Details

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Balance Type:	credit
Period Type:	instant

- 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 the fixed and determinable portion of the unrecorded unconditional purchase obligation maturing after the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- 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://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 440
-SubTopic 10
-Section 50
-Paragraph 4
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=77896938&loc=d3e25336-109308

+ Details

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Contingencies And Commitments (Guarantees) (Details) $ in Millions	12 Months Ended
	Dec. 31, 2019 USD ($) $ / MW MW	Dec. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)
Guarantees
Guarantees And Other Contingencies [Line Items]
Expiration Date	indefinite
Maximum Obligation	$ 36
Carrying Amount	$ 0
Guarantees \| Consumers Energy Company
Guarantees And Other Contingencies [Line Items]
Expiration Date	indefinite
Maximum Obligation	$ 30
Carrying Amount	$ 0
Indemnity Obligations From Stock And Asset Sales Agreements
Guarantees And Other Contingencies [Line Items]
Expiration Date	indefinite
Maximum Obligation	$ 153
Carrying Amount	2
Tax And Other Indemnity Obligations \| Consumers Energy Company
Guarantees And Other Contingencies [Line Items]
Carrying Amount	1
MCV PPA \| Consumers Energy Company
Guarantees And Other Contingencies [Line Items]
Total	3,295
2020	313
2021	287
2022	272
2023	225
2024	201
Beyond 2024	$ 1,997
Term of unrecorded PPA	35 years
PPA minimum quantity required \| MW	1,240
PPA capacity charge per MWh (in dollars per MWh) \| $ / MW	10.14
Annual contribution to renewable resources program by counterparty	$ 5
Contract extension period	5 years
Purchases	$ 318	$ 353	$ 321
Palisades PPA \| Consumers Energy Company
Guarantees And Other Contingencies [Line Items]
Total	899
2020	388
2021	398
2022	113
2023	0
2024	0
Beyond 2024	0
Purchases	395	375	366
Related-party PPAs \| Consumers Energy Company
Guarantees And Other Contingencies [Line Items]
Total	472
2020	71
2021	72
2022	74
2023	74
2024	75
Beyond 2024	106
Other PPAs \| Consumers Energy Company
Guarantees And Other Contingencies [Line Items]
Total	4,670
2020	258
2021	278
2022	291
2023	309
2024	329
Beyond 2024	3,205
Purchases	336	$ 350	$ 349
Total PPAs \| Consumers Energy Company
Guarantees And Other Contingencies [Line Items]
Total	9,336
2020	1,030
2021	1,035
2022	750
2023	608
2024	605
Beyond 2024	5,308
Other
Guarantees And Other Contingencies [Line Items]
Total	3,244
2020	1,685
2021	520
2022	451
2023	210
2024	199
Beyond 2024	179
Other \| Consumers Energy Company
Guarantees And Other Contingencies [Line Items]
Total	2,865
2020	1,638
2021	477
2022	413
2023	174
2024	162
Beyond 2024	$ 1
Palisades Power Purchase Agreement \| Financing Obligation \| Consumers Energy Company
Guarantees And Other Contingencies [Line Items]
Annual average capacity (in MW) \| MW	798