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Income Tax (Narrative) (Details) - USD ($) $ in Thousands | 12 Months Ended
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Dec. 31, 2022 | Dec. 31, 2021 | Dec. 31, 2020
Income Tax Disclosure [Abstract] |  |  |
Unrecognized tax position | $ 0 | $ 0 |
Interest and penalties on unrecognized tax benefits | 0 | 0 |
Federal operating loss carryforwards, set to begin to expire in 2024 | 9,900 |  |
Idaho state operating loss carryforwards, set to begin to expire in 2024 | 5,400 |  |
State operating loss carryforwards, set to begin to expire in 2024 | 25 |  |
Proportional amortization as a component of income tax expense | 1,800 | 916 | $ 622
Affordable Housing Tax Credits and Other Tax Benefits, Amount | 2,000 | 1,200 | $ 738
Low-income housing tax credit investments | 47,200 | 24,000 |
Qualified Affordable Housing Project Investments, Commitment | $ 41,300 | $ 19,200 |

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- Definition Idaho state operating loss carryforwards, set to begin to expire in 2024 + References No definition available. + Details
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- Definition Low-income housing tax credit investments + References No definition available. + Details
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- Definition Amount of affordable housing tax credits and other tax benefits recognized. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 323 -SubTopic 740 -Section 50 -Paragraph 2 -Subparagraph (a) -URI https://asc.fasb.org/extlink&oid=116633289&loc=SL49122993-202985 + Details
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- Definition Amount of deferred tax liability not recognized because of the exceptions to comprehensive recognition of deferred taxes related to undistributed earnings of domestic subsidiaries. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 30 -Section 50 -Paragraph 2 -Subparagraph (d) -URI https://asc.fasb.org/extlink&oid=6424122&loc=d3e41874-109331 + Details
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- Definition Amount of commitment or contingent commitments to qualified affordable housing project investments. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 323 -SubTopic 740 -Section 50 -Paragraph 2 -Subparagraph (e) -URI https://asc.fasb.org/extlink&oid=116633289&loc=SL49122993-202985 + Details
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- Definition Amount of expense for interest on an underpayment of income taxes and penalties related to a tax position claimed or expected to be claimed in the tax return. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 15 -Subparagraph (c) -URI https://asc.fasb.org/extlink&oid=121826272&loc=d3e32718-109319 + Details
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