Consolidated Statements of Stockholders' Equity - USD ($) $ in Thousands	Total	Common Stock	Additional Paid-in Capital	Retained Earnings	Common Stock (Acquired from) Sold to Stock- holders	Accumulated Other Comprehensive Earnings (Losses)	Common Stock Related to ESOP
Beginning Balance at Dec. 28, 2013	$ 7,894,239	$ 776,721	$ 1,898,974	$ 7,454,448	$ 0	$ 86,999	$ (2,322,903)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Comprehensive earnings	1,757,443			1,735,308		22,135
Dividends per share	(577,227)			(577,227)
Contribution of shares to retirement plans	309,714	8,063	235,362		66,289
Acquisition of shares from stockholders	(688,339)				(688,339)
Sale of shares to stockholders	284,105	2,168	66,556		215,381
Retirement of shares	0	(12,480)		(394,189)	406,669
Change for ESOP related shares	(357,625)						(357,625)
Ending Balance at Dec. 27, 2014	8,622,310	774,472	2,200,892	8,218,340	0	109,134	(2,680,528)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Comprehensive earnings	1,882,182			1,965,048		(82,866)
Dividends per share	(612,766)			(612,766)
Contribution of shares to retirement plans	332,559	6,172	247,139		79,248
Acquisition of shares from stockholders	(855,801)				(855,801)
Sale of shares to stockholders	345,319	2,756	108,360		234,203
Retirement of shares	0	(13,225)		(529,125)	542,350
Change for ESOP related shares	(273,350)						(273,350)
Ending Balance at Dec. 26, 2015	9,440,453	770,175	2,556,391	9,041,497	0	26,268	(2,953,878)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Comprehensive earnings	2,022,847			2,025,688		(2,841)
Dividends per share	(667,902)			(667,902)
Contribution of shares to retirement plans	354,214	5,216	239,436		109,562
Acquisition of shares from stockholders	(960,262)				(960,262)
Sale of shares to stockholders	330,040	1,283	54,120		274,637
Retirement of shares	0	(13,476)		(562,587)	576,063
Change for ESOP related shares	(114,219)						(114,219)
Ending Balance at Dec. 31, 2016	$ 10,405,171	$ 763,198	$ 2,849,947	$ 9,836,696	$ 0	$ 23,427	$ (3,068,097)

Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income, attributable to parent entity. Excludes changes in equity resulting from investments by owners and distributions to owners.

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