Consolidated Balance Sheets - USD ($) shares in Thousands, $ / shares in Thousands, $ in Thousands	Dec. 31, 2022	Dec. 31, 2021
Current assets:
Cash and cash equivalents	$ 29,270	$ 18,559
Accounts receivable	168,906	101,495
Accrued unbilled revenue	89,048	82,169
Allowance for uncollectible accounts	(3,296)	(2,018)
Regulatory assets	117,491	72,391
Derivative instruments	194,412	48,130
Inventories	87,096	57,262
Other current assets	61,286	59,288
Total current assets	744,213	437,276
Non-current assets:
Property, plant, and equipment	4,261,566	3,997,243
Less: Accumulated depreciation	1,147,166	1,125,873
Total property, plant, and equipment, net	3,114,400	2,871,370
Regulatory Assets, Noncurrent	340,432	314,579
Derivative instruments	5,045	10,730
Other investments	95,704	89,278
Operating lease right of use asset	73,429	75,049
Assets under sales-type leases	134,302	138,995
Goodwill	149,283	70,570
Other non-current assets	91,518	56,757
Total non-current assets	4,004,113	3,627,328
Total assets	4,748,326	4,064,604
Current liabilities:
Short-term debt	258,200	389,500
Current maturities of long-term debt	90,697	345
Accounts payable	180,667	133,486
Taxes accrued	15,625	15,520
Interest accrued	10,169	7,503
Regulatory liabilities	248,582	112,281
Derivative instruments	28,728	10,402
Operating lease liabilities	1,514	1,296
Other current liabilities	64,552	54,432
Total current liabilities	898,734	724,765
Long-term debt	1,246,167	1,044,587
Deferred credits and other non-current liabilities:
Deferred Income Tax Liabilities, Net	366,022	340,231
Regulatory liabilities	689,578	658,332
Pension and other postretirement benefit liabilities	149,143	166,684
Derivative instruments	20,838	412
Operating lease liabilities	78,965	79,468
Other non-current liabilities	123,438	114,979
Total deferred credits and other non-current liabilities	1,427,984	1,360,106
Commitments and contingencies (see Note 16 and Note 17)
Equity:
Common stock - no par value	805,253	590,771
Retained earnings	376,473	355,779
Accumulated other comprehensive loss	(6,285)	(11,404)
Total equity	1,175,441	935,146
Total liabilities and equity	$ 4,748,326	$ 4,064,604
Par Value (in dollars per share)	$ 0	$ 0
Shares Authorized (in shares)	100,000	100,000
Shares issued (in shares)	35,525	31,129
Shares outstanding (in shares)	35,525	31,129
Northwest Natural Gas Company [Member]
Current assets:
Cash and cash equivalents	$ 12,977	$ 12,271
Accounts receivable	165,607	99,780
Accrued unbilled revenue	87,482	82,028
Receivables from affiliates	634	261
Allowance for uncollectible accounts	(3,079)	(1,962)
Regulatory assets	117,491	72,391
Derivative instruments	194,236	48,130
Inventories	86,207	56,752
Other current assets	57,269	47,378
Total current assets	718,824	417,029
Non-current assets:
Property, plant, and equipment	4,148,547	3,931,640
Less: Accumulated depreciation	1,137,231	1,119,361
Total property, plant, and equipment, net	3,011,316	2,812,279
Regulatory Assets, Noncurrent	340,407	314,539
Derivative instruments	5,045	10,730
Other investments	80,110	74,786
Operating lease right of use asset	72,720	74,987
Assets under sales-type leases	134,302	138,995
Other non-current assets	89,994	55,027
Total non-current assets	3,733,894	3,481,343
Total assets	4,452,718	3,898,372
Current liabilities:
Short-term debt	170,200	245,500
Current maturities of long-term debt	89,942	0
Accounts payable	177,590	131,475
Payables to affiliates	9,175	1,248
Taxes accrued	15,426	15,476
Interest accrued	8,900	7,296
Regulatory liabilities	248,553	112,281
Derivative instruments	28,728	10,402
Operating lease liabilities	1,363	1,273
Other current liabilities	62,019	53,591
Total current liabilities	811,896	578,542
Long-term debt	1,035,935	986,495
Deferred credits and other non-current liabilities:
Deferred Income Tax Liabilities, Net	362,353	337,717
Regulatory liabilities	688,599	657,350
Pension and other postretirement benefit liabilities	149,143	166,684
Derivative instruments	20,838	412
Operating lease liabilities	78,345	79,431
Other non-current liabilities	114,527	113,934
Total deferred credits and other non-current liabilities	1,413,805	1,355,528
Commitments and contingencies (see Note 16 and Note 17)
Equity:
Common stock - no par value	614,903	435,515
Retained earnings	582,593	553,696
Accumulated other comprehensive loss	(6,414)	(11,404)
Total equity	1,191,082	977,807
Total liabilities and equity	$ 4,452,718	$ 3,898,372