Rent Expense (Detail) (USD $)	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011
Rent Expense [Line Items]
Annual Rent	$ 650,000	$ 601,000
Auburn, Washington
Rent Expense [Line Items]
Annual Rent	25,000
Lease Expiration Date	Month to Month
Baton Rouge, Louisiana
Rent Expense [Line Items]
Annual Rent	27,000
Lease Expiration Date	Month to Month
Champaign, Illinois
Rent Expense [Line Items]
Annual Rent	258,000
Lease Expiration Date	Dec. 31, 2014
Charlotte, North Carolina
Rent Expense [Line Items]
Annual Rent	61,000
Lease Expiration Date	Mar. 31, 2016
Hampstead, New Hampshire
Rent Expense [Line Items]
Annual Rent	24,000
Lease Expiration Date	Aug. 31, 2017
Pearl River, New York
Rent Expense [Line Items]
Annual Rent	105,000
Lease Expiration Date	Aug. 31, 2018
Pottsboro, Texas
Rent Expense [Line Items]
Annual Rent	18,000
Lease Expiration Date	Aug. 31, 2014
Stony Point, New York
Rent Expense [Line Items]
Annual Rent	106,000
Lease Expiration Date	Jun. 30, 2016
Tulsa, Oklahoma
Rent Expense [Line Items]
Annual Rent	$ 26,000
Lease Expiration Date	Dec. 31, 2014