0001733998 2026-08-05 2026-08-05 0001733998 nwn:NorthwestNaturalGasCompanyMember 2026-08-05 2026-08-05 0001733998 0000073020 false false 8-K 8-K 2026-08-05 2026-08-05 NORTHWEST NATURAL HOLDING COMPANY NORTHWEST NATURAL GAS COMPANY 1-38681 1-15973 OR 82-4710680 OR 93-0256722 250 SW Taylor Street 250 SW Taylor Street Portland OR 97204 Portland OR 97204 (503) 226-4211 (503) 226-4211 false false false false false false false false Common Stock NWN NYSE false false