Trust Preferred Securities - Additional Information (Detail) (USD $)	1 Months Ended	6 Months Ended
	May 31, 2013	Jun. 30, 2013
Interest rate swap [Member]
Financial Instruments Subject to Mandatory Redemption by Settlement Terms [Line Items]
Loss on Trust Preferred Securities hedge	$ 1,900,000
Interest rate swap maturity date		Jan. 07, 2019
Trust Preferred Securities [Member]
Financial Instruments Subject to Mandatory Redemption by Settlement Terms [Line Items]
Aggregate principal balance		20,000,000
Maturity date		Oct. 07, 2033
Liquidation amount of trust preferred security		$ 1,000
Redemption date		Jul. 07, 2013
Redemption in securities		619,000
Settlement date		Jul. 08, 2013
Forecast [Member] | Subsequent Event [Member] | Interest rate swap [Member]
Financial Instruments Subject to Mandatory Redemption by Settlement Terms [Line Items]
Expected amount of savings in interest expense in remainder of current fiscal year		600,000
Expected amount of savings in interest expense annually through maturity date		$ 1,100,000
London Interbank Borrowing Rate (LIBOR) [Member]
Financial Instruments Subject to Mandatory Redemption by Settlement Terms [Line Items]
Description of interest rate		(LIBOR) plus 3.05% per annum, or 3.33%