Fair Value Option - Additional Information (Details) - Loans Receivable [Member] - USD ($)	Sep. 30, 2015	Dec. 31, 2014
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Nonaccrual loans	$ 19,000,000	$ 0
Nonaccrual loans, unpaid principal balance	22,000,000
Accruing loans contractually past due 90 days or more	$ 0	$ 0

Fair Value, Option, Loans Held as Assets, Aggregate Amount in Nonaccrual Status, Unpaid Principal Balance

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

This item represents the aggregate fair value of loans held as assets that are 90 days or more past due for which the fair value option has been elected.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 825

-SubTopic 10

-Section 50

-Paragraph 28

-Subparagraph (e)(1)

-URI http://asc.fasb.org/extlink&oid=6957238&loc=d3e14064-108612

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

This item represents the aggregate fair value of loans held as assets that are in nonaccrual status for which the fair value option has been elected, if the entity's policy is to recognize interest income separately from other changes in fair value.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 825

-SubTopic 10

-Section 50

-Paragraph 28

-Subparagraph (e)(2)

-URI http://asc.fasb.org/extlink&oid=6957238&loc=d3e14064-108612

+ Details

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Period Type:	instant

- Details

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