Deposits - Additional Information (Detail) (USD $) In Millions, unless otherwise specified	12 Months Ended
Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Disclosure Deposits [Line Items]
Demand Deposit Overdrafts Reclassified As Loan	$ 1.3	$ 2.0
Percentage of time deposits over total deposits	7.00%
Interest expense on time deposits of $100,000 or more	$ 1.7	$ 2.4	$ 3.3

Interest expense incurred on time deposits, including certificates of deposits, of $100,000 or more in domestic offices.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 225

-Section S99

-Paragraph 1

-Subparagraph (SX 210.9-04.6)

-URI http://asc.fasb.org/extlink&oid=6879574&loc=d3e536633-122882

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 04

-Paragraph 6

-Article 9

Name:	us-gaap_InterestExpenseTimeDeposits100000OrMore
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration