Long-Term Borrowings - Summary of Long -Term Borrowings (Detail) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012
Line of Credit Facility [Line Items]
Long-term borrowings	$ 55,110	$ 75,220
FNBB [Member]
Line of Credit Facility [Line Items]
Long-term borrowings	110	220
Credit Suisse Securities (USA) LLC [Member]
Line of Credit Facility [Line Items]
Long-term borrowings	55,000	55,000
Comerica [Member]
Line of Credit Facility [Line Items]
Long-term borrowings		$ 20,000