Loans and Allowance for Loan Losses - Summary of Nonperforming Loan Portfolio (Detail) - USD ($) $ in Thousands	9 Months Ended	12 Months Ended
Dec. 31, 2018	Dec. 31, 2019
Financing Receivable, Recorded Investment [Line Items]
Recorded Investment, With related allowance	$ 47,974	$ 62,493
Unpaid principal balance, With related allowance	49,188	62,964
Related allowance, With related allowance	29,147	15,156
Average investment recorded, With related allowance	72,253	61,109
Interest income (expense) recognized, With related allowance	1,070	1,209
Recreation [Member]
Financing Receivable, Recorded Investment [Line Items]
Recorded Investment, With related allowance	5,788	8,262
Unpaid principal balance, With related allowance	5,788	8,262
Related allowance, With related allowance	204	329
Average investment recorded, With related allowance	6,165	8,317
Interest income (expense) recognized, With related allowance	357	471
Home Improvement [Member]
Financing Receivable, Recorded Investment [Line Items]
Recorded Investment, With related allowance	137	185
Unpaid principal balance, With related allowance	137	185
Related allowance, With related allowance	3	3
Average investment recorded, With related allowance	137	185
Commercial [Member]
Financing Receivable, Recorded Investment [Line Items]
Recorded Investment, With related allowance	3,834	11,862
Unpaid principal balance, With related allowance	3,929	11,867
Average investment recorded, With related allowance	6,036	7,886
Interest income (expense) recognized, With related allowance	(12)	392
Medallion [Member]
Financing Receivable, Recorded Investment [Line Items]
Recorded Investment, With related allowance	38,215	42,184
Unpaid principal balance, With related allowance	39,334	42,650
Related allowance, With related allowance	28,940	14,824
Average investment recorded, With related allowance	59,915	44,721
Interest income (expense) recognized, With related allowance	$ 725	$ 346

Impaired financing receivable with related allowance interest income and adjusted interest expense accrual method.

No definition available.

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- Definition

Impaired Financing Receivables With Related Allowance Related Allowance

+ References

No definition available.

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- Definition

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.

+ References

No definition available.

+ Details

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- Definition

Amount of average investment of impaired financing receivables for which there is a related allowance for credit losses.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 15
-Subparagraph (c)(1)
-URI http://asc.fasb.org/extlink&oid=118936363&loc=d3e5212-111524

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 17
-URI http://asc.fasb.org/extlink&oid=118936363&loc=d3e5258-111524

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- Definition

Amount of investment in impaired financing receivables for which there is a related allowance for credit losses.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 14A
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=118936363&loc=SL6953550-111524

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- Definition

Unpaid principal balance of impaired financing receivables for which there is a related allowance for credit losses.

+ References

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