Consolidated Balance Sheets - USD ($) $ in Thousands		Jun. 30, 2021	Dec. 31, 2020
Current assets
Cash and cash equivalents		$ 305,573	$ 444,922
Accounts receivable, net		519,116	452,880
Other current assets		61,562	45,262
Total current assets		886,251	943,064
Property, plant, and equipment
Cost		12,677,327	12,641,745
Less accumulated depreciation		4,087,362	3,931,800
Net property, plant, and equipment		8,589,965	8,709,945
Goodwill		4,783	4,783
Other intangible assets		760,576	776,409
Equity investments		1,195,456	1,224,813
Other assets	[1]	189,268	171,013
Total assets	[2]	11,626,299	11,830,027
Current liabilities
Accounts and imbalance payables		246,790	210,691
Short-term debt		588,373	438,870
Accrued ad valorem taxes		35,570	41,427
Accrued liabilities		255,938	269,947
Total current liabilities		1,126,671	960,935
Long-term liabilities
Long-term debt		6,835,838	7,415,832
Deferred income taxes		23,468	22,195
Asset retirement obligations		267,624	260,283
Other liabilities		319,825	275,570
Total long-term liabilities		7,446,755	7,973,880
Total liabilities	[3]	8,573,426	8,934,815
Equity and partners' capital
Common units (413,076,351 and 413,839,863 units issued and outstanding at June 30, 2021, and December 31, 2020, respectively)		2,927,066	2,778,339
General partner units (9,060,641 units issued and outstanding at June 30, 2021, and December 31, 2020)		(13,923)	(17,208)
Total partners' capital		2,913,143	2,761,131
Noncontrolling interests		139,730	134,081
Total equity and partners' capital		3,052,873	2,895,212
Total liabilities, equity, and partners' capital		$ 11,626,299	$ 11,830,027
Common units issued		413,076,351	413,839,863
Common units outstanding		413,076,351	413,839,863
General partner units issued		9,060,641	9,060,641
General partner units outstanding		9,060,641	9,060,641

[1] Other assets includes $7.7 million and $4.2 million of NGLs line-fill inventory as of June 30, 2021, and December 31, 2020, respectively. Other assets also includes $60.3 million and $71.9 million of materials and supplies inventory as of June 30, 2021, and December 31, 2020, respectively.

[2] Total assets includes related-party amounts of $1.6 billion as of June 30, 2021, and December 31, 2020, which includes related-party Accounts receivable, net of $278.9 million and $291.3 million as of June 30, 2021, and December 31, 2020, respectively. See Note 6.

[3] Total liabilities includes related-party amounts of $222.8 million and $164.7 million as of June 30, 2021, and December 31, 2020, respectively. See Note 6.