Equity - Narrative - USD ($) $ / shares in Units, $ in Thousands |
3 Months Ended | 6 Months Ended | |||
|---|---|---|---|---|---|
Jun. 30, 2024 |
Jun. 30, 2024 |
Jun. 30, 2023 |
Dec. 31, 2023 |
Dec. 31, 2021 |
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| Class of Stock [Line Items] | |||||
| Par Value (in dollars per share) | $ 0 | $ 0 | $ 0 | $ 0 | |
| Shares issued (in shares) | 38,669,098 | 38,669,098 | 36,064,625 | 37,631,212 | |
| Proceeds from common stock issued, net | $ 34,986 | $ 22,072 | |||
| Avion Water | Other Northwest Holdings [Member] | |||||
| Class of Stock [Line Items] | |||||
| Investment balance in Avion | $ 14,500 | ||||
| ATM Equity Program | |||||
| Class of Stock [Line Items] | |||||
| Par Value (in dollars per share) | $ 0 | $ 0 | |||
| Sale of Stock, Consideration Received on Transaction | $ 22,800 | $ 35,000 | |||
| Sale of Stock, Commissions and Fees Paid | $ 300 | $ 600 | |||
| Stock Issued During Period, Shares, New Issues | 620,000 | 953,000 | |||
| nwn:AttheMarketEquityProgramEquityAvailableforIssuance | $ 7,900 | $ 7,900 | |||
| Maximum [Member] | Scenario, Plan | ATM Equity Program | |||||
| Class of Stock [Line Items] | |||||
| Cumulative Proceeds Received on All Transactions | $ 200,000 | ||||
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- Definition At the Market Equity Program, Available for Issuance No definition available.
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- Definition Cumulative amount of cash and other consideration received in exchange for shares or stock issued or sold. Include amounts of cash received, fair value of non-cash assets received, fair value of liabilities assumed, and fair value of any other forms of consideration. No definition available.
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- Definition Sale of Stock, Commissions and Fees Paid No definition available.
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- Definition Sale of Stock, Consideration Received No definition available.
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. Reference 1: http://www.xbrl.org/2003/role/exampleRef
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- Definition Face amount per share of no-par value common stock. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Total number of common shares of an entity that have been sold or granted to shareholders (includes common shares that were issued, repurchased and remain in the treasury). These shares represent capital invested by the firm's shareholders and owners, and may be all or only a portion of the number of shares authorized. Shares issued include shares outstanding and shares held in the treasury. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition This item represents the entity's ownership percentage in the investee multiplied by the investee's total equity. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition The cash inflow from the additional capital contribution to the entity. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Number of new stock issued during the period. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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