Nature of Business	12 Months Ended
Dec. 31, 2012
Nature of Business [Abstract]
Nature of Business	A. Nature of Business MicroFinancial Incorporated (referred to as “MicroFinancial,” “we,” “us” or “our”) operates primarily through its wholly-owned subsidiaries, TimePayment Corp. and Leasecomm Corporation. TimePayment is a specialized commercial/consumer finance company that leases and rents microticket equipment and provides other financing services. Leasecomm stared originating leases in 1986, but suspended virtually all originations in 2002 due to an interruption in financing. The average amount financed by TimePayment during 2012 was approximately $5,100 while Leasecomm historically financed contracts of approximately $1,900. We primarily source our originations through a nationwide network of independent equipment vendors, sales organizations and other dealer-based origination networks. We fund our operations through cash provided by operating activities and borrowings under our line of credit.

The entire disclosure for the nature of an entity's business, the major products or services it sells or provides and its principal markets, including the locations of those markets. If the entity operates in more than one business, the disclosure also indicates the relative importance of its operations in each business and the basis for the determination (for example, assets, revenues, or earnings).

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 275

-SubTopic 10

-Section 50

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=6927468&loc=d3e6003-108592

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher AICPA

-Name Statement of Position (SOP)

-Number 94-6

-Paragraph 10

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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