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Fair Value Measurements - Fair Value Measurement and Assumptions (Details) - USD ($)	3 Months Ended	9 Months Ended	12 Months Ended
	Sep. 30, 2025	Sep. 30, 2025	Dec. 31, 2024
Assumptions used in discounted cash flow model to determine fair value of investments classified within level 3
Doubtful and Impaired commercial collateral dependent loans	$ 153,318,000	$ 153,318,000	$ 168,621,000
Impaired commercial collateral dependent receivables appraisals to determine fair value within immediately preceding twelve months	71,882,000	71,882,000	110,583,000
Impaired collateral dependent commercial loans with internal evaluation completed within last twelve months	0	0	0
Charges to allowance for probable loan losses in connection with other real estate owned	0	46,000	2,228,000
Adjustment to fair value in connection with other real estate owned	1,255,000	1,275,000	632,000
Fair Value, Measurements, Nonrecurring
Assumptions used in discounted cash flow model to determine fair value of investments classified within level 3
Change in net provision, impaired loans	2,378,000	2,378,000	14,662,000
Change in net provision, other real estate owned	1,275,000	1,275,000	632,000
Fair Value, Measurements, Nonrecurring | Estimated Fair Value
Assets:
Watch-List doubtful loans	25,064,000	25,064,000	169,246,000
Non-financial assets:
Other real estate owned	4,819,000	4,819,000	11,537,000
Fair Value, Measurements, Nonrecurring | Estimated Fair Value | Fair Value, Inputs, Level 3
Assets:
Watch-List doubtful loans	25,064,000	25,064,000	169,246,000
Non-financial assets:
Other real estate owned	$ 4,819,000	$ 4,819,000	$ 11,537,000

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Amount of increase (decrease) of allowance reserve for credit losses in connection with loans transferred to other real estate owned.

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Reflects the amount of charge-off related to a loan prior to foreclosure.

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Carrying amount as of the balance sheet date of change in Provision of other real estate and foreclosed assets. Other real estate may include real estate investments, real estate loans that qualify as investments in real estate. Foreclosed assets include all assets obtained in full or partial satisfaction of a debt arrangement through foreclosure proceedings.

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The estimated fair value of the watch-list doubtful loans measured on a non-recurring basis as of the reporting date.

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The impaired collateral dependent commercial loans where an internal evaluation has been done in the last twelve months.

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The estimated fair value of the recorded impaired collateral measured on a non-recurring basis as of the reporting date.

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Carrying amount as of the balance sheet date of other real estate and foreclosed assets. Other real estate may include real estate investments, real estate loans that qualify as investments in real estate. Foreclosed assets include all assets obtained in full or partial satisfaction of a debt arrangement through foreclosure proceedings.

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