Deposits - Additional Information (Detail) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Cash And Short Term Investments [Line Items]
Aggregate amount of time deposits in denominations of $250000 or more	$ 19,200	$ 20,300
Overdraft demand deposits reclassified to loans	51	56
Wholesale deposits	$ 8,500	$ 15,500

The aggregate of all domestic and foreign interest-bearing deposit liabilities.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.12)
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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