CONSOLIDATED BALANCE SHEETS (Parenthetical) - USD ($) $ in Thousands	Jun. 30, 2019	Dec. 31, 2018
CURRENT ASSETS:
Trade receivables, allowances	$ 2,656	$ 2,355
OTHER ASSETS:
Intangibles, accumulated amortization	$ 56,289	$ 49,136
STOCKHOLDERS’ EQUITY:
Preferred stock shares authorized (in shares)	5,000,000	5,000,000
Preferred stock shares issued (in shares)	0	0
Common stock shares authorized (in shares)	100,000,000	100,000,000
Common stock shares issued (in shares)	55,079,000	54,893,000
Common stock shares outstanding (in shares)	55,079,000	54,893,000
Developed technology
OTHER ASSETS:
Intangibles, accumulated amortization	$ 125,447	$ 102,357
Other
OTHER ASSETS:
Intangibles, accumulated amortization	$ 56,289	$ 49,136