Subsequent Events	6 Months Ended
	Jun. 30, 2022
Subsequent Events [Abstract]
Subsequent Events [Text Block]	SUBSEQUENT EVENTOn July 15, 2022, NW Natural entered into a Bond Purchase Agreement between NW Natural and the institutional investors named as purchasers therein (the Bond Purchase Agreement). The Bond Purchase Agreement provides for the issuance of $140.0 million aggregate principal amount of NW Natural's First Mortgage Bonds, 4.78% Series due 2052 (the Bonds). The Bonds are expected to be issued on or about September 30, 2022. The Bonds will bear interest at the rate of 4.78% per annum, payable semi-annually on March 30 and September 30 of each year, commencing March 30, 2023, and will mature on September 30, 2052.The Bonds will be subject to redemption prior to maturity at the option of NW Natural, in whole or in part, (i) at any time prior to March 30, 2052, at a redemption price equal to 100% of the principal amount thereof plus a “make-whole” premium and accrued and unpaid interest thereon to the date of redemption, and (ii) at any time on and after March 30, 2052, at 100% of the principal amount thereof plus accrued and unpaid interest thereon to the date of redemption.