Subsequent Events	3 Months Ended
Mar. 31, 2022
Subsequent Events [Abstract]
Subsequent Events [Text Block]	SUBSEQUENT EVENTOn April 1, 2022, NW Holdings issued and sold 2,875,000 shares of its common stock pursuant to a registration statement on Form S-3 and related prospectus settlement. NW Holdings received net offering proceeds, after deducting the underwriter's discounts and commissions and estimated expenses payable by NW Holdings, of approximately $138.6 million. The proceeds are to be used for general corporate purposes, including repayment of its short-term indebtedness and/or making equity contributions to NW Holdings' subsidiaries, NW Natural, NW Natural Water and NW Natural Renewables. Contributions to NW Natural, NW Natural Water and NW Natural Renewables are to be used for general corporate purposes. Of the contributions received by NW Natural, $130.0 million was used to repay its short-term indebtedness.

The entire disclosure for significant events or transactions that occurred after the balance sheet date through the date the financial statements were issued or the date the financial statements were available to be issued. Examples include: the sale of a capital stock issue, purchase of a business, settlement of litigation, catastrophic loss, significant foreign exchange rate changes, loans to insiders or affiliates, and transactions not in the ordinary course of business.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 855
-URI http://asc.fasb.org/topic&trid=2122774

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 855
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=6842918&loc=SL6314017-165662

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