Revision of Previously Issued Financial Statements - Consolidated Statements of Cash Flows (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2020	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Cash flows from operating activities:
Net income	$ (1,756)	$ (1,678)	$ (2,023)	$ 4	$ 4,585	$ 11,847	$ (2,511)	$ (6,056)	$ (5,455)	$ 7,864	$ 3,044
Changes in operating assets and liabilities:
Contract assets									(191)	1,740	(2,167)
Income taxes payable									(5,642)	158	(2,682)
Net cash provided by operating activities									$ 14,922	18,244	1,226
As Previously Reported
Cash flows from operating activities:
Net income										8,789	3,846
Changes in operating assets and liabilities:
Contract assets										655	(3,110)
Income taxes payable										318	(2,541)
Net cash provided by operating activities										18,244	1,226
Adjustment
Cash flows from operating activities:
Net income					$ 500					(925)	(802)
Changes in operating assets and liabilities:
Contract assets										1,085	943
Income taxes payable										$ (160)	$ (141)