Goodwill and Other Intangible Assets (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended	12 Months Ended
	Dec. 02, 2017	Dec. 02, 2017	Mar. 04, 2017
Finite Lived And Indefinite Lived Intangible Assets By Major Class
Goodwill, impairment charges	$ 0	$ 0	$ 0
Gross Carrying Amount of Finite Lived	1,896,375	1,896,375	1,894,061
Accumulated Amortization	(1,311,601)	(1,311,601)	(1,212,155)
Net	584,774	584,774	681,906
Gross Carrying Amount of Indefinite Lived	33,500	33,500
Gross Carrying Amount, Total	1,929,875	1,929,875	1,927,561
Net, Total	618,274	618,274	715,406
Trademarks
Finite Lived And Indefinite Lived Intangible Assets By Major Class
Gross Carrying Amount of Indefinite Lived	33,500	33,500	33,500
Favorable leases and other
Finite Lived And Indefinite Lived Intangible Assets By Major Class
Gross Carrying Amount of Finite Lived	384,937	384,937	386,636
Accumulated Amortization	(318,634)	(318,634)	(308,766)
Net	66,303	$ 66,303	$ 77,870
Remaining Weighted Average Amortization Period		7 years	7 years
Prescription files
Finite Lived And Indefinite Lived Intangible Assets By Major Class
Gross Carrying Amount of Finite Lived	898,351	$ 898,351	$ 894,330
Accumulated Amortization	(795,003)	(795,003)	(764,840)
Net	103,348	$ 103,348	$ 129,490
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	465,000	$ 465,000	$ 465,000
Accumulated Amortization	(157,639)	(157,639)	(110,653)
Net	307,361	$ 307,361	$ 354,347
Remaining Weighted Average Amortization Period		15 years	16 years
CMS license
Finite Lived And Indefinite Lived Intangible Assets By Major Class
Gross Carrying Amount of Finite Lived	57,500	$ 57,500	$ 57,500
Accumulated Amortization	(5,597)	(5,597)	(3,872)
Net	51,903	$ 51,903	$ 53,628
Remaining Weighted Average Amortization Period		23 years	24 years
Claims adjudication and other developed software
Finite Lived And Indefinite Lived Intangible Assets By Major Class
Gross Carrying Amount of Finite Lived	58,987	$ 58,987	$ 58,995
Accumulated Amortization	(20,509)	(20,509)	(14,188)
Net	38,478	$ 38,478	$ 44,807
Remaining Weighted Average Amortization Period		5 years	6 years
Trademarks
Finite Lived And Indefinite Lived Intangible Assets By Major Class
Gross Carrying Amount of Finite Lived	20,100	$ 20,100	$ 20,100
Accumulated Amortization	(4,891)	(4,891)	(3,383)
Net	15,209	$ 15,209	$ 16,717
Remaining Weighted Average Amortization Period		8 years	9 years
Backlog
Finite Lived And Indefinite Lived Intangible Assets By Major Class
Gross Carrying Amount of Finite Lived	11,500	$ 11,500	$ 11,500
Accumulated Amortization	(9,328)	(9,328)	(6,453)
Net	$ 2,172	$ 2,172	$ 5,047
Remaining Weighted Average Amortization Period		1 year	2 years