Variable Interest Entity Arrangements (Schedule of Assets and Liabilities) (Details) - USD ($) $ in Thousands	Mar. 31, 2022	Dec. 31, 2021
Current assets:
Cash and cash equivalents	$ 88,259	$ 64,140
Accounts receivable, net of allowance for doubtful accounts	58,583	87,248
Prepaid expenses and other	3,024	5,542
Total current assets	149,866	156,930
Property and equipment:
Gas gathering and processing equipment	0	274,748
Transportation equipment	1,826	4,550
Property, plant, and equipment, gross	303,511	579,423
Less accumulated depreciation, depletion, amortization, and impairment	80,694	128,880
Net property and equipment	222,817	450,543
Operating right of use asset	8,151	12,445
Other assets	7,093	9,559
Total assets	389,585	629,477
Current liabilities:
Accounts payable	26,330	58,625
Accrued liabilities	19,169	22,450
Current operating lease liability	1,949	3,791
Current portion of other long-term liabilities	4,537	5,574
Total current liabilities	187,287	151,138
Total long-term operating lease payments	6,244	8,677
Long-term debt (Note 9)	$ 0	19,200
VIE
Current assets:
Cash and cash equivalents		17,246
Accounts receivable, net of allowance for doubtful accounts		42,628
Prepaid expenses and other		1,263
Total current assets		61,137
Property and equipment:
Gas gathering and processing equipment		274,748
Transportation equipment		2,801
Property, plant, and equipment, gross		277,549
Less accumulated depreciation, depletion, amortization, and impairment		53,792
Net property and equipment		223,757
Operating right of use asset		3,485
Other assets		2,226
Total assets		290,605
Current liabilities:
Accounts payable		34,010
Accrued liabilities		5,292
Current operating lease liability		1,450
Current portion of other long-term liabilities		1,548
Total current liabilities		42,300
Total long-term operating lease payments		2,036
Total liabilities		63,536
Long-term debt (Note 9)		$ 19,200