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Other Commitments And Contingencies (Narrative) (Details) $ in Millions | 3 Months Ended | 31 Months Ended |
--- | --- | --- | ---
Mar. 31, 2022 USD ($) Rate | Mar. 31, 2021 USD ($) | Dec. 31, 2021 USD ($)
Other Commitments And Contingencies [Line Items] |  |  |
Guaranty Liabilities | $ 485.2 |  |
Recorded reserves to cover environmental remediation at various sites | $ 91.3 |  | $ 91.1
Wind Power Purchase Agreement, Purchase Percentage | Rate | 100.00% |  |
Proceeds from Legal Settlements | $ 105.0 |  |
MGP Sites |  |  |
Other Commitments And Contingencies [Line Items] |  |  |
Number of waste disposal sites identified by program | 53 |  |
Liability for Estimated Remediation Costs | $ 84.8 |  | 85.1
Reasonably possible remediation costs variance from reserve | 17.0 |  |
Columbia Of Massachusetts |  |  |
Other Commitments And Contingencies [Line Items] |  |  |
Pipeline Replacement Expenses |  | $ 258.0 |
Standby Letters of Credit |  |  |
Other Commitments And Contingencies [Line Items] |  |  |
Long-term Line of Credit | $ 14.4 |  | $ 18.9

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- Definition Total costs accrued as of the balance sheet date for environmental loss contingencies. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 450 -SubTopic 20 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=121557415&loc=d3e14326-108349 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 450 -SubTopic 20 -Section 25 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=6395460&loc=d3e13647-108346 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 410 -SubTopic 30 -Section 50 -Paragraph 7 -URI http://asc.fasb.org/extlink&oid=6393242&loc=d3e13207-110859 + Details
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