Consolidated Balance Sheets - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Current assets:
Cash and cash equivalents	$ 140,733	$ 129,625
Restricted cash	653	658
Short-term investments	186,142	189,771
Accounts receivable, net	87,491	79,991
Contract assets	20,558	21,246
Inventories	156,216	145,906
Deferred cost of sales	596	433
Prepaid expenses and other current assets	25,778	19,301
Total current assets	618,167	586,931
Property, plant, and equipment, net	65,207	65,271
Operating lease right-of-use assets	29,548	10,275
Intangible assets, net	42,831	46,185
Goodwill	181,943	181,943
Deferred income taxes	1,440	1,440
Other assets	6,106	6,019
Total assets	945,242	898,064
Current liabilities:
Accounts payable	42,638	33,656
Accrued expenses and other current liabilities	51,064	44,876
Customer deposits and deferred revenue	68,907	67,235
Income taxes payable	1,086	914
Total current liabilities	163,695	146,681
Deferred income taxes	5,236	5,240
Long-term debt	324,629	321,115
Operating lease long-term liabilities	31,421	6,305
Other liabilities	7,800	10,349
Total liabilities	532,781	489,690
Stockholders' equity:
Preferred stock, $0.01 par value; 500,000 shares authorized; no shares issued and outstanding.
Common stock, $0.01 par value; 120,000,000 shares authorized; 50,182,609 shares issued and outstanding at March 31, 2021 and 49,723,751 shares issued and outstanding at December 31, 2020	502	497
Additional paid-in capital	1,114,959	1,113,352
Accumulated deficit	(704,827)	(707,321)
Accumulated other comprehensive income	1,827	1,846
Total stockholders' equity	412,461	408,374
Total liabilities and stockholders' equity	$ 945,242	$ 898,064