Accounts Receivable, net - Summary of accounts receivable, net (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Government segment:
Accounts receivable-net	$ 41,774	$ 26,219
Government
Government segment:
Accounts receivable-net	11,000	8,537
Government \| Billed
Government segment:
Accounts receivable-net	11,608	9,100
Government \| Advanced billings
Government segment:
Accounts receivable-net	(608)	(563)
Restaurant/Retail
Government segment:
Accounts receivable-net	$ 30,774	$ 17,682

Amount, after allowance for credit loss, of right to consideration from customer for product sold and service rendered in normal course of business, classified as current.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
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