Medallion Bank - Schedule of Balance Sheet and Net Investment (Parenthetical) (Detail) $ in Thousands	Dec. 31, 2017 USD ($)
Medallion Financing Trust I [Member]
Debt Securities, Available-for-sale [Line Items]
Unrealized appreciation	$ 152,267
Small Business Lending Fund Program [Member]
Debt Securities, Available-for-sale [Line Items]
Preferred stock issued	$ 26,303

This element represents the excess of the cost (face amount, notional amount) of an investment (security, contract) over its fair value which deficiency has not been recognized in earnings of the entity.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 946
-SubTopic 320
-Section S99
-Paragraph 22
-URI http://asc.fasb.org/extlink&oid=50485924&loc=SL6090603-123010

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- Definition

Aggregate par or stated value of issued nonredeemable preferred stock (or preferred stock redeemable solely at the option of the issuer). This item includes treasury stock repurchased by the entity. Note: elements for number of nonredeemable preferred shares, par value and other disclosure concepts are in another section within stockholders' equity.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(28))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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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.

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- Details

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