Other Borrowings - Summary of Balances of Other Borrowings (Parenthetical) (Detail) (Other collateralized borrowings, fixed rate, as of September 30, 2014 of 0.05%, payable on October 1, 2014 [Member])	9 Months Ended
	Sep. 30, 2014
Other collateralized borrowings, fixed rate, as of September 30, 2014 of 0.05%, payable on October 1, 2014 [Member]
Debt Instrument [Line Items]
FHLB borrowings fixed rate	0.05%
FHLB fixed rate borrowings maturity date	Oct. 01, 2014