Goodwill and Other Intangible Assets - Intangibles (Details) - USD ($) $ in Thousands	3 Months Ended		12 Months Ended
	May 29, 2021	May 30, 2020	Feb. 27, 2021
Finite Lived And Indefinite Lived Intangible Assets By Major Class
Goodwill impairment	$ 0
Accumulated impairment losses	574,712		$ 574,712
Gross Carrying Amount, Finite Lived	1,737,198		1,733,101
Accumulated Amortization	(1,425,716)		(1,406,982)
Net	311,482		326,119
Gross Carrying Amount, Total	1,751,598		1,747,501
Net, Total	325,882		340,519
Other intangibles, net	325,882		340,519
Trademarks
Finite Lived And Indefinite Lived Intangible Assets By Major Class
Gross Carrying Amount, Indefinite Lived	14,400		14,400
Impairment of intangible assets		$ 29,852
Noncompete agreements and other
Finite Lived And Indefinite Lived Intangible Assets By Major Class
Gross Carrying Amount, Finite Lived	195,238		193,916
Accumulated Amortization	(174,573)		(172,618)
Net	$ 20,665		$ 21,298
Remaining Weighted Average Amortization Period	3 years		3 years
Prescription files
Finite Lived And Indefinite Lived Intangible Assets By Major Class
Gross Carrying Amount, Finite Lived	$ 1,025,975		$ 1,023,200
Accumulated Amortization	(907,329)		(900,321)
Net	$ 118,646		$ 122,879
Remaining Weighted Average Amortization Period	6 years		6 years
Customer relationships
Finite Lived And Indefinite Lived Intangible Assets By Major Class
Gross Carrying Amount, Finite Lived	$ 388,000		$ 388,000
Accumulated Amortization	(268,674)		(261,584)
Net	$ 119,326		$ 126,416
Remaining Weighted Average Amortization Period	10 years		11 years
CMS license
Finite Lived And Indefinite Lived Intangible Assets By Major Class
Gross Carrying Amount, Finite Lived	$ 57,500		$ 57,500
Accumulated Amortization	(13,646)		(13,072)
Net	$ 43,854		$ 44,428
Remaining Weighted Average Amortization Period	19 years		20 years
Claims adjudication and other developed software
Finite Lived And Indefinite Lived Intangible Assets By Major Class
Gross Carrying Amount, Finite Lived	$ 58,985		$ 58,985
Accumulated Amortization	(49,994)		(47,887)
Net	$ 8,991		$ 11,098
Remaining Weighted Average Amortization Period	1 year		2 years
Backlog
Finite Lived And Indefinite Lived Intangible Assets By Major Class
Gross Carrying Amount, Finite Lived	$ 11,500		$ 11,500
Accumulated Amortization	$ (11,500)		$ (11,500)
Remaining Weighted Average Amortization Period	0 years		0 years