Debt

6 Months Ended

Jun. 30, 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:

	June 30,				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	(10,141)		(7,938)		(8,823)
Carrying amount	$	1,324,559	$	986,762	$	1,125,877
Estimated fair value(1)	$	1,176,519	$	891,064	$	944,383
NW Holdings:
Gross long-term debt	$	1,545,553	$	1,053,912	$	1,345,851
Unamortized debt issuance costs	(10,261)		(8,031)		(8,987)
Carrying amount	$	1,535,292	$	1,045,881	$	1,336,864
Estimated fair value(1)	$	1,385,612	$	950,597	$	1,148,395

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