Details Derivative Positions (Detail) (USD $) In Thousands, unless otherwise specified	9 Months Ended	12 Months Ended
	Sep. 30, 2013	Dec. 31, 2012
Derivative [Line Items]
Notional Amount	$ 15,000	$ 15,000
Trade Date	Dec. 13, 2012	Dec. 13, 2012
Effective Date	Nov. 30, 2015	Nov. 30, 2015
Maturity Date	Nov. 28, 2022	Nov. 28, 2022
Receive (Variable) Index	US 3-Month LIBOR	US 3-Month LIBOR
Current Project Receive Rate	3.301%	2.338%
Pay Fixed Swap Rate	2.376%	2.376%
Fair Value of Derivative Position	$ 889	$ (36)