Investments in Unconsolidated Affiliates (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2022 USD ($) item mi	Dec. 31, 2021 USD ($)	Dec. 31, 2020 USD ($)	Dec. 31, 2019 USD ($)
Investments in unconsolidated affiliates
Balance at beginning of period	$ 696,009	$ 722,478
Additional investments		2,070
Equity in earnings of unconsolidated affiliates	94,218	90,451	$ 86,430
Distributions from unconsolidated affiliates	(120,460)	(118,990)	(98,858)
Return of investment in unconsolidated affiliate	(17,000)
Balance at end of period	652,767	696,009	722,478
Summarized Financial Information of Unconsolidated Affiliates
Current assets	88,993	83,804
Total assets	5,791,320	5,544,001
Current liabilities	102,077	114,009
Partners' capital	2,192,318	2,286,698	2,418,286	$ 3,143,414
Total liabilities and stockholders' equity	5,791,320	5,544,001
Revenues	919,985	898,202	900,719
Income from operations	539,466	555,327	(117,638)
Net income attributable to unconsolidated affiliates, including noncontrolling interest	326,242	331,617	(122,527)
Unconsolidated Affiliates
Summarized Financial Information of Unconsolidated Affiliates
Current assets	74,852	74,704
Noncurrent assets	1,517,349	1,602,093
Total assets	1,592,201	1,676,797
Current liabilities	5,453	8,375
Noncurrent liabilities	4,427	4,827
Noncontrolling interest	154,100	161,842
Partners' capital	1,428,221	1,501,753
Total liabilities and stockholders' equity	1,592,201	1,676,797
Revenues	357,730	333,565	321,880
Operating expenses	153,383	130,080	122,660
Income from operations	204,347	203,485	199,220
Net income attributable to unconsolidated affiliates, including noncontrolling interest	248,458	236,444	230,564
Net income attributable to unconsolidated affiliates	$ 257,458	245,256	238,991
Stonewall
Equity Method Investments
Ownership percentage	15.00%
Number of miles of pipeline | mi	67
Investments in unconsolidated affiliates
Balance at beginning of period	$ 130,572	137,632
Equity in earnings of unconsolidated affiliates	7,558	6,560
Distributions from unconsolidated affiliates	(12,015)	(13,620)
Balance at end of period	$ 126,115	130,572	137,632
MarkWest Joint Venture
Equity Method Investments
Ownership percentage	50.00%
Percentage of interest held by joint venture in third party fractionator in Ohio	33.33%
Number of fractionators | item	2
Investments in unconsolidated affiliates
Balance at beginning of period	$ 565,437	584,846
Additional investments		2,070
Equity in earnings of unconsolidated affiliates	86,660	83,891
Distributions from unconsolidated affiliates	(108,445)	(105,370)
Return of investment in unconsolidated affiliate	(17,000)
Balance at end of period	$ 526,652	$ 565,437	$ 584,846