Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Statement of Financial Position [Abstract]
Accounts receivable, allowances	$ 329	$ 269
Property and equipment, accumulated depreciation	60,120	58,633
Intangible assets, accumulated amortization	$ 4,029	$ 3,150
Common stock, par value (in dollars per share)	$ 0.0001	$ 0.0001
Common stock, shares authorized (in shares)	190,000,000	190,000,000
Common stock, shares issued (in shares)	38,473,000	38,084,000
Common stock, shares outstanding (in shares)	38,473,000	38,084,000