Business Segment Information (Details) - USD ($)	3 Months Ended
	Mar. 28, 2017	Mar. 29, 2016	Dec. 27, 2016	Dec. 29, 2015
Segment Reporting Information [Line Items]
Refranchising loss	$ 0	$ 1,071,000
Revenues:
Total revenues	727,633,000	685,153,000
Segment profit:
Total segment profit	161,291,000	141,866,000
Depreciation and amortization	40,555,000	36,257,000
Unallocated General and Administrative Expenses	49,241,000	48,182,000
Pre-opening expenses	1,367,000	2,196,000
Interest expense	3,117,000	1,739,000
Other (income) expense, net	2,782,000	(251,000)
Income before income taxes	65,607,000	55,143,000
Capital expenditures:
Capital Expenditures	42,329,000	50,573,000
Segment Assets
Unallocated cash and cash equivalents	153,355,000	159,985,000	$ 105,529,000	$ 241,886,000
Unallocated trade and other accounts receivable	49,750,000		53,519,000
Unallocated property and equipment	806,078,000		802,759,000
Total assets	1,299,361,000		1,301,611,000
Company bakery cafe operations [Member]
Revenues:
Total revenues	636,012,000	598,784,000
Franchise operations [Member]
Revenues:
Total revenues	40,369,000	37,852,000
Operating Segments [Member]
Segment profit:
Depreciation and amortization	40,555,000
Unallocated Amount to Segment [Member]
Segment profit:
Unallocated General and Administrative Expenses	47,863,000	46,782,000
Segment Assets
Unallocated cash and cash equivalents	153,355,000		105,529,000
Unallocated trade and other accounts receivable	6,059,000		6,691,000
Unallocated property and equipment	119,305,000		117,178,000
Unallocated deposits and other	5,077,000		5,285,000
Other unallocated assets	8,061,000		18,775,000
Operating Segments [Member]
Segment Assets
Total assets	1,007,504,000		1,048,153,000
Operating Segments [Member] | Company bakery cafe operations [Member]
Revenues:
Total revenues	636,012,000	598,784,000
Segment profit:
Total segment profit	114,973,000	99,115,000
Depreciation and amortization	29,572,000	27,697,000
Capital expenditures:
Capital Expenditures	32,874,000	34,878,000
Segment Assets
Total assets	902,279,000		942,653,000
Operating Segments [Member] | Franchise operations [Member]
Revenues:
Total revenues	40,369,000	37,852,000
Segment profit:
Total segment profit	38,991,000	36,452,000
Segment Assets
Total assets	19,042,000		18,301,000
Operating Segments [Member] | Fresh dough and other product operations [Member]
Revenues:
Total revenues	102,453,000	95,899,000
Segment profit:
Total segment profit	7,327,000	6,299,000
Depreciation and amortization	2,689,000	2,105,000
Capital expenditures:
Capital Expenditures	2,732,000	5,925,000
Segment Assets
Total assets	86,183,000		$ 87,199,000
Operating Segments [Member] | Corporate Administration [Member]
Segment profit:
Depreciation and amortization	8,294,000	6,455,000
Capital expenditures:
Capital Expenditures	6,723,000	9,770,000
Intersegment Eliminations [Member] | Intersegment Eliminations [Member]
Revenues:
Total revenues	$ (51,201,000)	$ (47,382,000)