XML 84 R70.htm IDEA: XBRL DOCUMENT
v3.20.4

Funds Borrowed - Schedule of Outstanding Balances of Funds Borrowed (Parenthetical) (Detail) - USD ($) | Dec. 31, 2020 | Dec. 31, 2019
--- | --- | ---
Debt Disclosure [Abstract] |  |
Deferred costs | $ 5,805,000 | $ 5,105,000
Reserve Deposits | $ 250,000 |

X
- Definition Reserve deposits. + References No definition available. + Details
Name: | mfin_ReserveDeposits
Namespace Prefix: | mfin_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- References No definition available. + Details
Name: | us-gaap_DebtDisclosureAbstract
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition The carrying amount of deferred costs. + References No definition available. + Details
Name: | us-gaap_DeferredCostsCurrentAndNoncurrent
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant