Accounts Receivable Factoring (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Accounts, Notes, Loans and Financing Receivable [Line Items]
Cash collected on behalf of factor	$ 1,786	$ 21,485
Continuing Involvement with Derecognized Transferred Financial Assets, Amount Outstanding	85,108	103,818
Amount Of Account Receivable Factoring Without Recourse	476,405	556,102
Loss On Sale Of Accounts Receivable Without Recourse	$ 776	$ 1,007	$ 1,248