Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Variable Interest Entity [Line Items]
Cash and cash equivalents	$ 1,368,318	$ 885,162
Accounts receivable: product and transportation	590,526	834,771
Inventories: materials, supplies and other	207,618	191,413
Prepayments and other	47,583	61,662
Properties, plants and equipment, at cost	7,299,517	7,237,297
Accumulated depreciation	(2,726,378)	(2,414,585)
Operating lease right-of-use assets	350,548	467,109
Goodwill	2,293,935	2,373,907
Intangibles and other	663,665	673,646
Accounts payable	1,000,959	1,215,555
Operating lease liabilities	97,937	104,415
Accrued liabilities	274,459	337,993
Long-term debt	3,142,718	2,455,640
Noncurrent operating lease liabilities	285,785	364,420
Deferred income taxes	713,703	889,270
Other long-term liabilities	$ 267,299	$ 260,157
Preferred stock par value (in USD per share)	$ 1.00	$ 1.00
Preferred stock, shares authorized (in shares)	5,000,000	5,000,000
Preferred stock, shares issued (in shares)	0	0
Common stock par value (in USD per share)	$ 0.01	$ 0.01
Common stock, shares authorized (in shares)	320,000,000	320,000,000
Common stock, shares issued (in shares)	256,046,051	256,042,554
Common stock held in treasury (in shares)	93,632,391	94,196,029
Variable Interest Entity
Variable Interest Entity [Line Items]
Cash and cash equivalents	$ 21,990	$ 13,287
Accounts receivable: product and transportation	14,543	18,732
Inventories: materials, supplies and other	895	833
Prepayments and other	8,591	6,795
Properties, plants and equipment, at cost	2,119,295	2,047,674
Accumulated depreciation	(644,149)	(552,786)
Operating lease right-of-use assets	2,979	2,652
Goodwill	312,873	312,873
Intangibles and other	365,773	319,569
Accounts payable	28,565	18,050
Operating lease liabilities	3,827	3,608
Accrued liabilities	29,518	30,418
Long-term debt	1,405,603	1,462,031
Noncurrent operating lease liabilities	68,454	72,000
Deferred income taxes	449	424
Other long-term liabilities	$ 55,105	$ 59,021