Debt and Financing Arrangements - Other Financing Obligations (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2023	Mar. 31, 2022	Dec. 31, 2022
Debt Instrument [Line Items]
Long-Term Debt	$ 5,248,807		$ 5,251,799
Long-term debt due within one year	29,183		28,532
Proceeds from other financing obligations	3,757	$ 2,843
Dalton Expansion Project
Debt Instrument [Line Items]
Long-Term Debt	248,700		249,400
Long-term debt due within one year	2,800		2,800
Atlantic Sunrise Project
Debt Instrument [Line Items]
Long-Term Debt	781,800		784,600
Long-term debt due within one year	25,300		24,600
Proceeds from other financing obligations	3,700	300
Leidy South Project
Debt Instrument [Line Items]
Long-Term Debt	76,000		76,200
Long-term debt due within one year	$ 1,100		$ 1,100
Proceeds from other financing obligations		$ 2,600

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No definition available.

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Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt, classified as current. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.19,20)
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Amount, excluding unamortized premium (discount) and debt issuance cost, of long-term debt classified as noncurrent. Excludes lease obligation.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(22))
-URI https://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

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Amount of cash inflow from issuance of long-term debt classified as other.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 14
-Subparagraph (b)
-URI https://asc.fasb.org/extlink&oid=126954810&loc=d3e3255-108585

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