Income Taxes: (Details) (USD $)	12 Months Ended
	Dec. 28, 2013	Dec. 29, 2012	Dec. 31, 2011
Income Taxes:
Federal statutory tax rate (as a percent)	35.00%
Reconciliation of the expected federal income tax expense based on the federal statutory tax rate to the actual income tax expense
Federal income tax expense at statutory rate (35%)	$ 10,356,500	$ 8,104,400	$ 8,183,600
Valuation allowance	7,300	1,413,600	577,700
State and local income taxes, net of federal benefit	886,200	677,700	827,700
Permanent differences, including stock option expenses	113,000	60,200	(223,600)
Other, net	(4,700)	(38,300)	(78,800)
Total provision for income taxes	11,358,300	10,217,600	9,286,600
Current provision for income taxes:
Federal	10,013,500	8,332,400	4,718,000
State	1,468,600	1,186,000	860,000
Foreign	375,400	374,900	377,000
Current provision	11,857,500	9,893,300	5,955,000
Deferred provision for income taxes:
Federal	(449,300)	435,300	2,890,500
State	(49,900)	(111,000)	441,100
Deferred provision	(499,200)	324,300	3,331,600
Total provision for income taxes	11,358,300	10,217,600	9,286,600
Deferred tax assets:
Accounts receivable and lease reserves	376,900	368,600
Accrued restructuring charge	64,600	64,500
Non-qualified stock option expense	946,000	901,800
Deferred franchise and software license fees	606,600	519,800
Trademarks	95,600	96,400
Lease deposits	1,263,600	1,093,200
Loss from and impairment of equity and note investments	4,081,600	4,074,300
Valuation allowance	(4,081,600)	(4,074,300)
Other	328,200	301,800
Total deferred tax assets	3,681,500	3,346,100
Deferred tax liabilities:
Lease revenue and initial direct costs	(9,101,900)	(9,267,900)
Depreciation and amortization	(224,600)	(222,400)
Total deferred tax liabilities	(9,326,500)	(9,490,300)
Total net deferred tax liabilities	(5,645,000)	(6,144,200)
Excess tax benefits related to stock option exercises	413,600	884,300	249,500
Unrecognized tax benefits, including interest and penalties	398,000	323,400
Interest and penalties accrued related to unrecognized tax benefit	14,300	11,100
Activity related to the company's unrecognized tax benefits
Balance at the beginning of the period	312,300	309,500
Increases related to current year tax positions	111,500	95,900
Additions for tax positions of prior years	17,700
Subtractions for tax positions of prior years		(2,800)
Expiration of the statute of limitations for the assessment of taxes	(57,800)	(90,300)
Balance at the end of the period	$ 383,700	$ 312,300	$ 309,500
Period over which various statutes of limitations are expected to expire	12 months