Goodwill and Other Intangible Assets (Details 2) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended		12 Months Ended
	Nov. 28, 2015	Nov. 29, 2014	Nov. 28, 2015	Nov. 29, 2014	Feb. 28, 2015
Finite Lived And Indefinite Lived Intangible Assets By Major Class
Gross Carrying Amount of Finite Lived	$ 2,965,763		$ 2,965,763		$ 2,093,531
Accumulated Amortization	(1,803,658)		(1,803,658)		(1,672,051)
Net	1,162,105		1,162,105		421,480
Gross Carrying Amount, Total	3,009,763		3,009,763		2,093,531
Net, Total	1,206,105		1,206,105		421,480
Unfavorable lease intangibles	49,649		49,649		55,571
Amortization expense for intangible assets and liabilities	54,338	$ 29,399	134,888	$ 87,167
Anticipated annual amortization expense for intangible assets and liabilities
2016	186,981		186,981
2017	213,616		213,616
2018	173,435		173,435
2019	137,411		137,411
2020	107,913		107,913
Trademarks
Finite Lived And Indefinite Lived Intangible Assets By Major Class
Gross Carrying Amount of Indefinite Lived	44,000		44,000
Favorable leases and other
Finite Lived And Indefinite Lived Intangible Assets By Major Class
Gross Carrying Amount of Finite Lived	666,635		666,635		653,377
Accumulated Amortization	(505,360)		(505,360)		(481,041)
Net	161,275		$ 161,275		$ 172,336
Remaining Weighted Average Amortization Period			8 years		8 years
Prescription files
Finite Lived And Indefinite Lived Intangible Assets By Major Class
Gross Carrying Amount of Finite Lived	1,518,028		$ 1,518,028		$ 1,440,154
Accumulated Amortization	(1,260,081)		(1,260,081)		(1,191,010)
Net	257,947		$ 257,947		$ 249,144
Remaining Weighted Average Amortization Period			3 years		3 years
Customer relationships
Finite Lived And Indefinite Lived Intangible Assets By Major Class
Gross Carrying Amount of Finite Lived	585,500		$ 585,500
Accumulated Amortization	(30,181)		(30,181)
Net	555,319		$ 555,319
Remaining Weighted Average Amortization Period			17 years
CMS license
Finite Lived And Indefinite Lived Intangible Assets By Major Class
Gross Carrying Amount of Finite Lived	108,000		$ 108,000
Accumulated Amortization	(1,872)		(1,872)
Net	106,128		$ 106,128
Remaining Weighted Average Amortization Period			25 years
Claims adjudication and other developed software
Finite Lived And Indefinite Lived Intangible Assets By Major Class
Gross Carrying Amount of Finite Lived	59,500		$ 59,500
Accumulated Amortization	(3,683)		(3,683)
Net	55,817		$ 55,817
Remaining Weighted Average Amortization Period			7 years
Trademarks
Finite Lived And Indefinite Lived Intangible Assets By Major Class
Gross Carrying Amount of Finite Lived	15,600		$ 15,600
Accumulated Amortization	(676)		(676)
Net	14,924		$ 14,924
Remaining Weighted Average Amortization Period			10 years
Backlog
Finite Lived And Indefinite Lived Intangible Assets By Major Class
Gross Carrying Amount of Finite Lived	12,500		$ 12,500
Accumulated Amortization	(1,805)		(1,805)
Net	$ 10,695		$ 10,695
Remaining Weighted Average Amortization Period			3 years