Investment in Leasing Operations: (Details 4) (Investment in leases, USD $)	6 Months Ended
Jun. 29, 2013	Jun. 30, 2012
Investment in leases
Activity in the allowance for credit losses for leasing operations
Balance at beginning of period	$ 775,800	$ 803,800
Provisions charged to expense	(37,900)	(67,900)
Recoveries	102,600	159,900
Deductions for amounts written-off	(17,300)	(110,000)
Balance at end of period	$ 823,200	$ 785,800

A valuation allowance for financing receivables that are expected to be uncollectible.

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-Name Accounting Standards Codification

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Amount of recovery of financing receivables doubtful of collection that were previously charged off.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef

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Amount of direct write-downs of financing receivables charged against the allowance.

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- Definition

The sum of the periodic provision charged to earnings, based on an assessment of uncollectibility from the counterparty on account of loan, lease or other credit losses, to reduce these accounts to the amount that approximates their net realizable value.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 95

-Paragraph 28

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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-Name Audit and Accounting Guide (AAG)

-Number AAG-DEP

-Paragraph 168, 169, 170

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