Accumulated Other Comprehensive Loss	3 Months Ended
Mar. 31, 2021
Equity [Abstract]
Accumulated Other Comprehensive Loss	Accumulated Other Comprehensive LossFor both the three months ended March 31, 2021 and March 31, 2020, we did not record any remeasurements related to the pension and other post-retirement benefits provided by Explorer and Colonial to their employees. We are not a sponsor of these benefits plans.

The entire disclosure for comprehensive income, which includes, but is not limited to, 1) the amount of income tax expense or benefit allocated to each component of other comprehensive income, including reclassification adjustments, 2) the reclassification adjustments for each classification of other comprehensive income and 3) the ending accumulated balances for each component of comprehensive income.

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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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-Name Accounting Standards Codification
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
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Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
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