Investment in Leasing Operations: (Details) (USD $)	Sep. 29, 2012	Dec. 31, 2011
Direct financing and sales-type leases:
Minimum lease payments receivable	$ 26,733,300	$ 27,413,300
Estimated residual value of equipment	2,501,900	2,764,400
Unearned lease income net of initial direct costs deferred	(4,647,100)	(4,217,000)
Security deposits	(2,651,000)	(2,448,800)
Equipment installed on leases not yet commenced	12,438,500	6,489,200
Total investment in direct financing and sales-type leases	34,375,600	30,001,100
Allowance for credit losses	(802,000)	(803,800)
Net investment in direct financing and sales-type leases	33,573,600	29,197,300
Operating leases:
Operating lease assets	1,349,400	1,218,900
Less accumulated depreciation and amortization	(785,000)	(567,300)
Net investment in operating leases	564,400	651,600
Total net investment in leasing operations	34,138,000	29,848,900
Net investment in leases - current	10,764,800	11,746,900
Net investment in leases - long-term	$ 23,373,200	$ 18,102,000