Consolidated Balance Sheets - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018
Current assets:
Cash and cash equivalents	$ 169,439	$ 212,273
Restricted cash	804	809
Short-term investments	67,215	48,189
Accounts receivable, net	74,860	66,808
Contract assets	10,479	10,397
Inventories	148,103	156,311
Deferred cost of sales	2,921	3,072
Prepaid expenses and other current assets	24,943	22,221
Total current assets	498,764	520,080
Property, plant, and equipment, net	77,737	80,284
Operating lease right-of-use-assets	12,874
Intangible assets, net	80,931	85,149
Goodwill	184,302	184,302
Deferred income taxes	1,869	1,869
Other assets	29,117	29,132
Total assets	885,594	900,816
Current liabilities:
Accounts payable	36,315	39,611
Accrued expenses and other current liabilities	44,040	46,450
Customer deposits and deferred revenue	68,881	72,736
Income taxes payable	792	1,256
Total current liabilities	150,028	160,053
Deferred income taxes	5,675	5,690
Long-term debt	290,473	287,392
Operating lease long-term liabilities	8,382
Other liabilities	9,238	9,906
Total liabilities	463,796	463,041
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; 48,675,196 and 48,547,417 shares issued at March 31, 2019 and December 31, 2018, respectively; 48,675,196 and 48,024,685 shares outstanding at March 31, 2019 and December 31, 2018, respectively	487	485
Additional paid-in capital	1,058,179	1,061,325
Accumulated deficit	(638,726)	(619,983)
Accumulated other comprehensive income	1,858	1,820
Treasury stock, at cost, 522,732 shares at December 31, 2018.		(5,872)
Total stockholders' equity	421,798	437,775
Total liabilities and stockholders' equity	$ 885,594	$ 900,816