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Fair Values - Additional Information (Detail) (USD $)	9 Months Ended	12 Months Ended
	Sep. 30, 2013	Dec. 31, 2012
Fair Value Inputs [Abstract]
Recorded cost of mortgage loans held for sale	$ 1,400,000	$ 3,500,000
Transfers in or out of level 1, level 2 or level 3	$ 0	$ 0

X

- Definition

Fair value transfers in or out of level one level two or level three.

+ References

No definition available.

+ Details

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Balance Type:	credit
Period Type:	duration

X

- Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
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Period Type:	duration

X

- Definition

Amount of mortgage loans held for sale. Excludes loans and leases covered under loss sharing agreements and loans classified as debt securities.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 45

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=28367877&loc=d3e4428-111522



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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.9-03.7(a)(3))

-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878



Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 948

-SubTopic 310

-Section 45

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6490309&loc=d3e48678-111004



Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Permanent Investor

-URI http://asc.fasb.org/extlink&oid=6520390

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