Contract Assets and Liabilities Changes in Net Contract Assets (Liabilities) (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Contract assets
Current	$ 1,238	$ 2,183
Non-Current		244
Contract assets	1,238	2,427
Contract Liabilities
Current	953	4,473
Non-current	293	383
Contract liabilities	$ 1,246	$ 4,856

Amount, after allowance for credit loss, of right to consideration in exchange for good or service transferred to customer when right is conditioned on something other than passage of time.

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