Transfers of Financial Assets (Reserve for loan repurchases) (Detail) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Valuation Allowance for Impairment of Recognized Servicing Assets [Roll Forward]
Beginning balance			$ 747	$ 508
Provision charged to expense			43	49
(Charge-offs/settlements) recoveries, net			(8)	98
Ending balance	$ 782	$ 655	$ 782	$ 655
SEC Schedule, 12-09, Reserve, Off-balance Sheet Activity [Member]
Valuation Allowance for Impairment of Recognized Servicing Assets [Roll Forward]
Beginning balance	770	633
Provision charged to expense	20	27
(Charge-offs/settlements) recoveries, net	$ (8)	$ (5)

Reflects the estimated amount of impairment as of the balance sheet date of recognized servicing assets that are being amortized in proportion to and over the period of estimated net servicing income or loss.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 50
-Section 50
-Paragraph 4
-Subparagraph (e)(1)
-URI http://asc.fasb.org/extlink&oid=125521744&loc=d3e122739-111746

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- Definition

Amount of increase in the valuation allowance for impairment of contract to service financial assets under which the benefits of servicing are expected to more than adequately compensate the servicer from charges to expense.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 50
-Section 50
-Paragraph 4
-Subparagraph (e)(2)
-URI http://asc.fasb.org/extlink&oid=125521744&loc=d3e122739-111746

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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ References

No definition available.

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- Definition

Valuation Allowance for Impairment of Recognized Servicing Assets, Additions (Deductions) for Recoveries (Charge-Offs and Settlements)

+ References

No definition available.

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