Condensed Consolidated Balance Sheets (unaudited) (Parenthetical) - USD ($) $ in Thousands	Mar. 31, 2018	Dec. 31, 2017
Allowance for doubtful accounts	$ 149	$ 0
Common Stock Class A
Common stock, no par (dollars per share)
Common stock, shares authorized	500,000,000
Common stock, shares issued	104,549,667
Common stock, shares outstanding	104,549,667
Common Stock Class B
Common stock, no par (dollars per share)
Common stock, shares authorized	20,000,000
Common stock, shares issued	4,455,208
Common stock, shares outstanding	4,455,208
Common Stock Class C
Common stock, no par (dollars per share)
Common stock, shares authorized	1,040,000,000
Common stock, shares issued	0
Common stock, shares outstanding	0