Consolidated Statement of Cash Flows - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2022	Sep. 30, 2021
Operating activities:
Net income	$ 38,367	$ 38,138
Adjustments to reconcile net income to cash provided by operations:
Depreciation	85,565	84,679
Regulatory amortization of gas reserves	4,527	11,606
Deferred income taxes	7,759	2,748
Qualified defined benefit pension plan expense	4,013	12,075
Contributions to qualified defined benefit pension plans	0	(9,590)
Deferred environmental expenditures, net	(14,437)	(14,952)
Environmental remediation expense	7,950	6,092
Asset optimization revenue sharing bill credits	(41,102)	(9,053)
Other	16,640	14,868
Changes in assets and liabilities:
Receivables, net	114,755	83,826
Inventories	(41,463)	(17,307)
Income and other taxes	19,447	19,620
Accounts payable	(30,010)	(18,057)
Deferred gas costs	(1,785)	(33,379)
Asset optimization revenue sharing	17,629	41,407
Decoupling mechanism	7,124	(9,172)
Change in Cloud-based software Assets	(17,332)	(6,851)
Other, net	(11,686)	(14,974)
Cash provided by operating activities	165,961	181,724
Investing activities:
Capital expenditures	(251,842)	(212,376)
Acquisitions, net of cash acquired	(2,352)	(375)
Proceeds from the sale of assets	539	2,712
Proceeds from Sale of Equity Method Investments	0	7,000
Other	(3,349)	(482)
Cash used in investing activities	(257,004)	(203,521)
Financing activities:
Proceeds from common stock issued, net	190,929	2,107
Long-term debt issued	290,000	55,000
Long-term debt retired	0	(95,000)
Proceeds from term loan due within one year	0	100,000
Repayment of commercial paper, maturities greater than three months	0	(195,025)
Changes in other short-term debt, net	(248,500)	190,000
Cash dividend payments on common stock	(46,434)	(41,827)
Other	(1,802)	(1,240)
Cash used in financing activities	184,193	14,015
Cash, cash equivalents and restricted cash	120,270	27,672
Increase (decrease) in cash, cash equivalents and restricted cash	93,150	(7,782)
Supplemental disclosure of cash flow information:
Interest paid, net of capitalization	31,774	30,910
Income taxes paid, net of refunds	2,106	6,980
Northwest Natural Gas Company [Member]
Operating activities:
Net income	41,343	39,682
Adjustments to reconcile net income to cash provided by operations:
Depreciation	83,166	82,418
Regulatory amortization of gas reserves	4,527	11,606
Deferred income taxes	7,013	1,687
Qualified defined benefit pension plan expense	4,013	12,075
Contributions to qualified defined benefit pension plans	0	(9,590)
Deferred environmental expenditures, net	(14,437)	(14,952)
Environmental remediation expense	7,950	6,092
Asset optimization revenue sharing bill credits	(41,102)	(9,053)
Other	16,665	13,728
Changes in assets and liabilities:
Receivables, net	115,915	84,726
Inventories	(40,881)	(17,317)
Income and other taxes	17,412	5,175
Accounts payable	(32,023)	(22,929)
Deferred gas costs	(1,785)	(33,379)
Asset optimization revenue sharing	17,629	41,407
Decoupling mechanism	7,124	(9,172)
Change in Cloud-based software Assets	(17,332)	(6,851)
Other, net	(12,604)	(13,525)
Cash provided by operating activities	162,593	161,828
Investing activities:
Capital expenditures	(236,467)	(199,399)
Proceeds from the sale of assets	539	2,712
Other	(3,349)	(482)
Cash used in investing activities	(239,277)	(197,169)
Financing activities:
Capital contributions from parent	179,388	2,135
Long-term debt issued	140,000	0
Long-term debt retired	0	(60,000)
Proceeds from term loan due within one year	0	100,000
Repayment of commercial paper, maturities greater than three months	0	(195,025)
Changes in other short-term debt, net	(192,500)	234,000
Cash dividend payments on common stock	(46,319)	(41,935)
Other	(1,617)	(1,706)
Cash used in financing activities	78,952	37,469
Cash, cash equivalents and restricted cash	23,100	17,867
Increase (decrease) in cash, cash equivalents and restricted cash	2,268	2,128
Supplemental disclosure of cash flow information:
Interest paid, net of capitalization	28,326	29,920
Income taxes paid, net of refunds	$ 5,990	$ 23,035