Debt

3 Months Ended

Mar. 31, 2023

Debt Disclosure [Abstract]

Schedule of Carrying Values and Estimated Fair Values of Debt Instruments

The following table provides an estimate of the fair value of long-term debt, including current maturities of long-term debt, using market prices in effect on the valuation date:

	March 31,				December 31,
In thousands	2023		2022		2022
NW Natural:
Gross long-term debt	$	1,334,700	$	994,700	$	1,134,700
Unamortized debt issuance costs	(10,278)		(8,073)		(8,823)
Carrying amount	$	1,324,422	$	986,627	$	1,125,877
Estimated fair value(1)	$	1,186,110	$	997,196	$	944,383
NW Holdings:
Gross long-term debt	$	1,545,730	$	1,053,177	$	1,345,851
Unamortized debt issuance costs	(10,428)		(8,171)		(8,987)
Carrying amount	$	1,535,302	$	1,045,006	$	1,336,864
Estimated fair value(1)	$	1,395,321	$	1,059,629	$	1,148,395

(1) Estimated fair value does not include unamortized debt issuance costs.