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The amount of net income (loss) for the period per each share of common stock or unit outstanding during the reporting period.

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The amount of net income (loss) for the period available to each share of common stock or common unit outstanding during the reporting period and to each share or unit that would have been outstanding assuming the issuance of common shares or units for all dilutive potential common shares or units outstanding during the reporting period.

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The portion of profit or loss for the period, net of income taxes, which is attributable to the parent, and includes adjustments resulting from the assumption that dilutive convertible securities were converted, options or warrants were exercised, or that other shares were issued upon the satisfaction of certain conditions.

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Net income after adjustments for dividends on preferred stock (declared in the period) and/or cumulative preferred stock (accumulated for the period).

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The sum of dilutive potential common shares or units used in the calculation of the diluted per-share or per-unit computation.

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Earnings Per Common Share (Reconciliation Of Numerators And Denominators Of Basic And Diluted Earnings Per Share) (Details) (USD $)	3 Months Ended								12 Months Ended
	Sep. 27, 2014	Jun. 28, 2014	Mar. 29, 2014	Dec. 28, 2013	Sep. 28, 2013	Jun. 29, 2013	Mar. 30, 2013	Dec. 29, 2012	Sep. 27, 2014	Sep. 28, 2013	Sep. 29, 2012
Class A Common Stock [Member]
Schedule Of Calculation Of Numerator And Denominator In Earnings Per Share [Line Items]
Net income allocated, basic									$ 31,776,515	$ 11,638,545	$ 24,151,777
Conversion of Class B to Class A shares									19,649,939	9,157,345	19,292,566
Net income allocated, diluted									51,426,454	20,795,890	43,444,343
Weighted average shares outstanding, basic									13,482,296	13,054,425	12,936,583
Conversion of Class B to Class A shares									9,126,381	10,817,989	11,364,899
Weighted average shares outstanding, diluted									22,608,677	23,872,414	24,301,482
Earnings per share, Basic	$ 0.82	$ 0.63	$ 0.47	$ 0.44	$ 0.71	$ (0.62)	$ 0.35	$ 0.50	$ 2.36	$ 0.89	$ 1.87
Earnings per share, Diluted	$ 0.79	$ 0.61	$ 0.46	$ 0.42	$ 0.68	$ (0.62)	$ 0.33	$ 0.48	$ 2.28	$ 0.87	$ 1.79
Class B Common Stock [Member]
Schedule Of Calculation Of Numerator And Denominator In Earnings Per Share [Line Items]
Net income allocated, basic									19,649,939	9,157,345	19,292,566
Net income allocated, diluted									$ 19,649,939	$ 9,157,345	$ 19,292,566
Weighted average shares outstanding, basic									9,126,381	10,817,989	11,364,899
Weighted average shares outstanding, diluted									9,126,381	10,817,989	11,364,899
Earnings per share, Basic	$ 0.74	$ 0.57	$ 0.43	$ 0.40	$ 0.65	$ (0.56)	$ 0.32	$ 0.45	$ 2.14	$ 0.85	$ 1.70
Earnings per share, Diluted	$ 0.74	$ 0.57	$ 0.43	$ 0.40	$ 0.65	$ (0.56)	$ 0.32	$ 0.45	$ 2.14	$ 0.85	$ 1.70