Future Maturities of Notes Payable (Detail) (USD $)	Jun. 30, 2013	Dec. 31, 2012
Debt Instrument [Line Items]
2014	$ 1,057,000
2015	122,000
2016	122,000
2017	122,000
2018 and thereafter	107,000
Total	1,530,000
Less: current portion	1,057,000	129,000
Note payable - noncurrent portion	$ 473,000	$ 560,000

Long term Debt, Maturities, Repayments of Principal in Year Five and Thereafter

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Carrying amount of long-term debt, net of unamortized discount or premium, including current and noncurrent amounts. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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Amount of long-term debt, sinking fund requirements, and other securities redeemable at fixed or determinable prices and dates maturing in the next fiscal year following the latest fiscal year.

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Amount of long-term debt, sinking fund requirements, and other securities redeemable at fixed or determinable prices and dates maturing in the fourth fiscal year following the latest fiscal year.

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Amount of long-term debt, sinking fund requirements, and other securities redeemable at fixed or determinable prices and dates maturing in the third fiscal year following the latest fiscal year.

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Amount of long-term debt, sinking fund requirements, and other securities redeemable at fixed or determinable prices and dates maturing in the second fiscal year following the latest fiscal year.

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Carrying value as of the balance sheet date of notes payable (with maturities initially due after one year or beyond the operating cycle if longer), excluding current portion.

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Sum of the carrying values as of the balance sheet date of the portions of long-term notes payable due within one year or the operating cycle if longer.

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