Amount of restructured debt contingently payable based on the occurrence of future events or circumstances.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 470

-SubTopic 60

-Section 50

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=6402221&loc=d3e15765-112638

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 15

-Paragraph 26

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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.

Name:	us-gaap_TroubledDebtRestructuringDebtorSubsequentPeriodsContingentPaymentsAmount
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

Loans - Additional Information (Detail) (USD $) In Thousands, unless otherwise specified				6 Months Ended
	Jun. 30, 2013 Loan	Dec. 31, 2012 Loan	Dec. 31, 2010	Jun. 30, 2013 Minimum [Member] CreditFacility	Jun. 30, 2013 Maximum [Member] CreditFacility
Financing Receivable, Modifications [Line Items]
Risk grade matrix scale				1	8
Number of Commercial loan	1	1
Troubled Debt Restructuring			$ 401