Stockholders' Equity And Stock-Based Compensation (Tables)

9 Months Ended

Sep. 30, 2017

Summary Of Stock Option Activity

	Stock Options Outstanding
			Weighted	Weighted average
	Number		average	remaining life
	of shares		exercise price	(in years)
Balances — December 31, 2016	1,229	$	3.82	7.6
Options granted	1,180		26.36
Options exercised	(70)		3.16
Options canceled	(12)		4.13
Options expired	—		—
Balances — September 30, 2017	2,327	$	15.27	8.4
Exercisable	721

Total Stock-Based Compensation Expense

	Three-Month Periods Ended				Nine-Month Periods Ended
	September 30,				September 30,
	2017		2016		2017		2016
General and administrative	$	2,778	$	183	$	5,287	$	478
Research and development		572		55		1,116		149
Total stock-based compensation expense	$	3,350	$	238	$	6,403	$	627

Schedule Of Fair Value Of Employee Stock Options

	Three-Month Periods Ended September 30,		Nine-Month Periods Ended September 30,
	2017	2016	2017	2016
Expected term in years	6.1	6.1	5.3 - 6.1	6.1
Expected volatility	80%	80%	80%	80%
Risk-free interest rate	1.8%	1.2%	1.8 - 2.1%	1.3%
Dividend yield	—	—	—	—

2017 Employee Stock Purchase Plan [Member]

Schedule Of Fair Value Of Employee Stock Options

	Three-Month Periods Ended September 30,		Nine-Month Periods Ended September 30,
	2017	2016	2017	2016
Expected term in years	0.5-  1.0	N/A	0.8 - 1.3	N/A
Expected volatility	95%	N/A	95%	N/A
Risk-free interest rate	1.1 - 1.2%	N/A	1.1 - 1.2%	N/A
Dividend yield	—	N/A	—	N/A