Goodwill and Other Intangible Assets - Intangibles (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended	12 Months Ended
	Nov. 30, 2019	Nov. 30, 2019	Mar. 02, 2019
Finite Lived And Indefinite Lived Intangible Assets By Major Class
Goodwill impairment	$ 0	$ 0
Accumulated impairment losses	574,712	574,712	$ 574,712
Gross Carrying Amount, Finite Lived	1,667,120	1,667,120	1,826,689
Accumulated Amortization	(1,311,960)	(1,311,960)	(1,397,483)
Net	355,160	355,160	429,206
Gross Carrying Amount, Total	1,686,620	1,686,620	1,846,189
Net, Total	374,660	374,660	448,706
Trademarks
Finite Lived And Indefinite Lived Intangible Assets By Major Class
Gross Carrying Amount, Indefinite Lived	19,500	19,500	19,500
Favorable leases and other
Finite Lived And Indefinite Lived Intangible Assets By Major Class
Gross Carrying Amount, Finite Lived	186,726	186,726	370,855
Accumulated Amortization	(163,426)	(163,426)	(318,503)
Net	23,300	$ 23,300	$ 52,352
Remaining Weighted Average Amortization Period		3 years	7 years
Prescription files
Finite Lived And Indefinite Lived Intangible Assets By Major Class
Gross Carrying Amount, Finite Lived	944,309	$ 944,309	$ 919,749
Accumulated Amortization	(858,393)	(858,393)	(827,222)
Net	85,916	$ 85,916	$ 92,527
Remaining Weighted Average Amortization Period		3 years	3 years
Customer relationships
Finite Lived And Indefinite Lived Intangible Assets By Major Class
Gross Carrying Amount, Finite Lived	388,000	$ 388,000	$ 388,000
Accumulated Amortization	(222,181)	(222,181)	(193,352)
Net	165,819	$ 165,819	$ 194,648
Remaining Weighted Average Amortization Period		12 years	13 years
CMS license
Finite Lived And Indefinite Lived Intangible Assets By Major Class
Gross Carrying Amount, Finite Lived	57,500	$ 57,500	$ 57,500
Accumulated Amortization	(10,197)	(10,197)	(8,472)
Net	47,303	$ 47,303	$ 49,028
Remaining Weighted Average Amortization Period		21 years	22 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	$ 58,985
Accumulated Amortization	(37,352)	(37,352)	(31,030)
Net	21,633	$ 21,633	$ 27,955
Remaining Weighted Average Amortization Period		3 years	4 years
Trademarks
Finite Lived And Indefinite Lived Intangible Assets By Major Class
Gross Carrying Amount, Finite Lived	20,100	$ 20,100	$ 20,100
Accumulated Amortization	(8,911)	(8,911)	(7,404)
Net	11,189	$ 11,189	$ 12,696
Remaining Weighted Average Amortization Period		6 years	7 years
Backlog
Finite Lived And Indefinite Lived Intangible Assets By Major Class
Gross Carrying Amount, Finite Lived	11,500	$ 11,500	$ 11,500
Accumulated Amortization	$ (11,500)	$ (11,500)	$ (11,500)
Remaining Weighted Average Amortization Period		0 years	0 years