| Investment [Table Text Block] |
Investments include gas reserves, financial investments in life insurance policies, and equity method investments. The following table summarizes other investments: | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | NW Holdings | | NW Natural | | June 30, | | December 31, | | June 30, | | December 31, | | In thousands | 2024 | | 2023 | | 2023 | | 2024 | | 2023 | | 2023 | | Investments in life insurance policies | $ | 46,295 | | | $ | 46,772 | | | $ | 45,713 | | | $ | 46,295 | | | $ | 46,772 | | | $ | 45,713 | | | Investments in gas reserves, non-current | 19,570 | | | 21,488 | | | 20,893 | | | 19,570 | | | 21,488 | | | 20,893 | | | Investment in unconsolidated affiliates | 17,930 | | | 36,070 | | | 36,345 | | | — | | | 19,588 | | | 19,539 | | | Total other investments | $ | 83,795 | | | $ | 104,330 | | | $ | 102,951 | | | $ | 65,865 | | | $ | 87,848 | | | $ | 86,145 | |
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