CONSOLIDATED BALANCE SHEETS - USD ($) $ in Thousands	Jun. 30, 2021	Dec. 31, 2020
Current assets:
Cash and cash equivalents	$ 53,337	$ 79,899
Restricted cash	1,422	1,422
Accounts receivable, net of allowances	58,746	78,614
Inventories	24,242	26,568
Prepaid expenses	8,774	6,044
Contract assets	21,828	18,579
Other current assets	2,265	2,366
Total current assets	170,614	213,492
Property and equipment, net	14,762	16,814
Goodwill	32,643	32,643
Right of use assets	26,561	29,430
Deferred tax assets, net	6,254	6,801
Other long-term assets	5,871	5,958
Total assets	256,705	305,138
Current liabilities:
Accounts payable	21,775	21,823
Accrued compensation and benefits	23,103	29,105
Accrued expenses and other current liabilities	32,904	42,264
Income taxes payable	1,648	1,664
Less: current portion	16,961	4,941
Deferred revenues	80,745	87,974
Total current liabilities	177,136	187,771
Long-term debt	165,178	202,759
Long-term deferred revenues	10,838	11,284
Long-term lease liabilities	25,819	28,462
Other long-term liabilities	7,476	7,786
Total liabilities	386,447	438,062
Commitments and Contingencies (Note 8)
Stockholders' deficit:
Common stock	452	442
Additional paid-in capital	1,029,675	1,036,658
Accumulated deficit	(1,156,950)	(1,168,347)
Accumulated other comprehensive loss	(2,919)	(1,677)
Total stockholders' deficit	(129,742)	(132,924)
Total liabilities and stockholders' deficit	$ 256,705	$ 305,138