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Contingencies And Commitments (Expected Remediation Cost By Year) (Details) $ in Millions | Mar. 31, 2018 USD ($)
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Bay Harbor [Member] |
Site Contingency [Line Items] |
Undiscounted amount due within one year | $ 3
Undiscounted amount due within two year | 4
Undiscounted amount due within third year | 4
Undiscounted amount due within fourth year | 4
Undiscounted amount due within five year | 4
Undiscounted amount due within six year | 4
Gas Utility [Member] | Manufactured Gas Plant [Member] | Consumers Energy Company [Member] |
Site Contingency [Line Items] |
Undiscounted amount due within one year | 15
Undiscounted amount due within two year | 18
Undiscounted amount due within third year | 10
Undiscounted amount due within fourth year | 18
Undiscounted amount due within five year | 7
Undiscounted amount due within six year | $ 2

X
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- Definition Undiscounted amount of the accrual for environmental loss contingencies expected to be paid 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://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 450 -SubTopic 20 -Section S99 -Paragraph 1 -Subparagraph (SAB Topic 5.Y.Q1) -URI http://asc.fasb.org/extlink&oid=27011672&loc=d3e149879-122751 + Details
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- Definition Undiscounted amount of the accrual for environmental loss contingencies expected to be paid 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 Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 450 -SubTopic 20 -Section S99 -Paragraph 1 -Subparagraph (SAB Topic 5.Y.Q1) -URI http://asc.fasb.org/extlink&oid=27011672&loc=d3e149879-122751 + Details
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- Definition Undiscounted amount of the accrual for environmental loss contingencies expected to be paid in the remainder of the 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 No definition available. + Details
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- Definition Undiscounted amount of the accrual for environmental loss contingencies expected to be paid 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 Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 450 -SubTopic 20 -Section S99 -Paragraph 1 -Subparagraph (SAB Topic 5.Y.Q1) -URI http://asc.fasb.org/extlink&oid=27011672&loc=d3e149879-122751 + Details
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- Definition Undiscounted amount of the accrual for environmental loss contingencies expected to be paid 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 Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 450 -SubTopic 20 -Section S99 -Paragraph 1 -Subparagraph (SAB Topic 5.Y.Q1) -URI http://asc.fasb.org/extlink&oid=27011672&loc=d3e149879-122751 + Details
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