Medicare Part D (Details) - USD ($) $ in Thousands		12 Months Ended
	Feb. 19, 2020	Feb. 29, 2020	Dec. 31, 2019	Mar. 02, 2019	Mar. 04, 2018	Mar. 03, 2018
Statutory Accounting Practices [Line Items]
Accounts receivable, net		$ 1,286,785		$ 1,788,712	$ 1,811,203	$ 1,869,100
Medicare Part D
Amount of receivables sold under Receivable Purchase Agreement	$ 501,422
Sale price for receivables sold	484,547
Receipts from sale of receivables	$ 449,949
Remaining receivable for receivables sold to third party		34,598
Loss on sale of receivable		16,875
Accrued salaries, wages and other current liabilities		746,318		808,439
EIC
Statutory Accounting Practices [Line Items]
Minimum amount of capital and surplus required by regulatory requirements			$ 20,195
Accounts receivable, net				$ 392,400
Medicare Part D
Accrued salaries, wages and other current liabilities		$ 14,083