Summary of Significant Accounting Policies - Additional Information (Detail) (USD $) In Millions, unless otherwise specified	6 Months Ended
Jun. 30, 2013 Loan	Jun. 30, 2012
Class of Stock [Line Items]
Highly liquid investments classified as cash equivalent, maturity period	3 months
Deposit return period	90 days
Minimum origination fee charged	1.11%	1.11%
Maximum origination fee charged	5.00%	5.00%
Maximum period for loan classified as non-accrual loan	120 days
Net Credit risk exposure on fair value of Member loans	$ 0.4
Maximum number of member loans borrower can have outstanding at one time	2
Vesting period	4 years
Computer Software, Intangible Asset
Class of Stock [Line Items]
Intangible assets, useful life	3 years
Minimum
Class of Stock [Line Items]
Property and equipment, estimated useful life	3 years
Maximum
Class of Stock [Line Items]
Property and equipment, estimated useful life	5 years

Highly Liquid Investments Maturity Period

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- Definition

Maximum number of member loans borrower can have outstanding at one time.

+ References

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- Definition

Maximum origination fee charged.

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- Definition

Maximum period for loan classified as nonaccrual loan.

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- Definition

Minimum origination fee charged.

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- Definition

Maximum amount of loss due to credit risk that, based on the gross fair value of the financial instrument, the entity would incur if parties to the financial instruments that make up the concentration failed completely to perform according to the terms of the contracts and the collateral or other security, if any, for the amount due proved to be of no value to the entity.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 825

-SubTopic 10

-Section 50

-Paragraph 21

-Subparagraph (b)

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- Definition

Useful life of finite-lived intangible assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Useful life of long lived, physical assets used in the normal conduct of business and not intended for resale, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Examples include, but not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment.

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Remaining recovery period of regulatory assets for which no return on investment during recovery period is provided, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 980

-SubTopic 340

-Section 50

-Paragraph 1

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- Definition

Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (a)(1)

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