Summary of Significant Accounting Policies Foreign Currency (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Component of Other Operating Cost [Line Items]
Other (Income) expense, net	$ 1,826	$ 5,319	$ (737)
Foreign Currency Gain (Loss) [Member]
Component of Other Operating Cost [Line Items]
Other (Income) expense, net	$ 1,160	$ 1,725	$ 2,598