For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

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Sum of the carrying amounts as of the balance sheet date of all investments.

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Amount before allowance of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Includes deferred interest and fees, undisbursed portion of loan balance, unamortized costs and premiums and discounts from face amounts. Excludes loans and leases covered under loss sharing agreements.

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The amount of loss pertaining to the specified contingency that was charged against earnings in the period, including the effects of revisions in previously reported estimates.

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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.

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Commitments and Contingencies - Narrative (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Jun. 30, 2017
Product Information [Line Items]
Commitments and contingencies, losses incurred	$ 0	$ 0	$ 0
Loans	883,757	869,730
U.S. Government and Government Sponsored Enterprises
Product Information [Line Items]
Investments	$ 223,500	$ 243,400
Loans secured by real estate \| Credit concentration risk \| Loans receivable
Product Information [Line Items]
Concentration risk, percentage	82.60%	88.30%
U.S. Government, Agencies, and Government Sponsored Enterprises securities \| Investment concentration Risk \| Investments
Product Information [Line Items]
Concentration risk, percentage	69.50%	77.70%
Real estate loans
Product Information [Line Items]
Loans	$ 730,200	$ 767,600