Loans - Additional Information (Detail)	6 Months Ended
Jun. 30, 2017
Minimum
Accounts, Notes, Loans and Financing Receivable [Line Items]
Number of days past due for a loan to remain on accrual status	90 days

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.

No definition available.

Name:	us-gaap_AccountsNotesAndLoansReceivableLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration