CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands		3 Months Ended
		Mar. 31, 2021	Mar. 31, 2020
Cash flows from operating activities:
Net income (loss) from operations		$ (9,151)	$ 4
Adjustments to reconcile net income (loss) from operations to net cash provided by (used in) operations:
Depreciation and amortization of intangible assets		2,310	3,019
Loss on disposal of assets		22	88
Deferred tax benefit		(732)	(306)
Stock-based compensation		1,342	1,350
Changes in operating assets and liabilities:
Accounts receivable, net		8,588	(1,817)
Inventories, net		1,748	1,445
Contract assets		2,346	(442)
Accounts payable		140	(1,663)
Income taxes payable		(1,634)	(4,735)
Accrued expenses		3,090	(2,104)
Deferred compensation		(1,527)	418
Deferred revenue		322	4,166
Other assets and liabilities		(3,281)	(1,775)
Net cash provided by operating activities		3,583	(2,352)
Cash flows from investing activities:
Purchase of short term investments		(25,234)	(6,642)
Maturities of short term investments		7,565	6,500
Additions to property and equipment		(755)	(1,516)
Other		(16)	(13)
Net cash provided by (used in) investing activities		(18,440)	(1,671)
Cash flows from financing activities:
Tax payments for restricted stock issuances		(2,139)	(293)
Net cash used in financing activities		(2,139)	(293)
Effect of exchange rate changes on cash		(558)	(342)
Net increase (decrease) in cash		(17,554)	(4,658)
Cash, cash equivalents, and restricted cash, beginning of period		89,241	85,129
Cash, cash equivalents, and restricted cash, end of period	[1]	71,687	80,471
Supplemental cash flow disclosures:
Restricted Cash		$ 900	$ 800

[1] End of period cash, cash equivalents, and restricted cash includes $0.9 million and $0.8 million of restricted cash at March 31, 2021 and March 31, 2020, respectively.