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Income Taxes - Additional Information (Details) - USD ($)	Jun. 30, 2025	Dec. 31, 2024
Income Taxes [Line Items]
Net deferred tax assets	$ 527,900,000	$ 456,400,000
Valuation allowance recorded	0	0
Bad debt reserves, created for tax purposes	58,600,000
Federal
Income Taxes [Line Items]
Operating loss carryforwards	183,100,000	60,200,000
Federal | Bremer
Income Taxes [Line Items]
Operating loss carryforwards	59,100,000
State
Income Taxes [Line Items]
Operating loss carryforwards	$ 148,400,000	$ 106,000,000.0

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- Definition

Income taxes.

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No definition available.

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Amount of bad debt reserves for tax purposes of qualified lenders excluded in calculating deferred taxes.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 942
-SubTopic 740
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 740
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-Paragraph 3
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-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482620/740-10-25-3

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Amount, after allocation of valuation allowances and deferred tax liability, of deferred tax asset attributable to deductible differences and carryforwards, without jurisdictional netting.

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Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 740
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
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Amount of deferred tax assets for which it is more likely than not that a tax benefit will not be realized.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 740
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
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Amount of operating loss carryforward, before tax effects, available to reduce future taxable income under enacted tax laws.

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