Other Receivables (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Accounts, Notes, Loans and Financing Receivable [Line Items]
Other receivables	$ 489,695	$ 469,796
Supplier rebates and non-trade receivables
Accounts, Notes, Loans and Financing Receivable [Line Items]
Other receivables	351,650	334,156
Medicare bad debt claims
Accounts, Notes, Loans and Financing Receivable [Line Items]
Other receivables	$ 138,045	$ 135,640