Other Receivables (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Accounts, Notes, Loans and Financing Receivable [Line Items]
Other receivables	$ 544,376	$ 489,695
Supplier rebates and non-trade receivables
Accounts, Notes, Loans and Financing Receivable [Line Items]
Other receivables	390,508	351,650
Medicare bad debt claims
Accounts, Notes, Loans and Financing Receivable [Line Items]
Other receivables	$ 153,868	$ 138,045