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Stockholders' Equity and Stock-Based Compensation - Additional Information (Details) - USD ($)	1 Months Ended		2 Months Ended	3 Months Ended		9 Months Ended
	Jun. 30, 2020	Mar. 31, 2020	Sep. 30, 2020	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019	May 29, 2020	May 28, 2020
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares issued in public offering (in shares)			202,503
Proceeds realized from offering			$ 4,900,000
Common stock authorized for issuance and sale			200,000,000.0	$ 200,000,000.0		$ 200,000,000.0
Availability remaining under the ATM program			$ 195,000,000.0	195,000,000.0		195,000,000.0
Stock-based compensation expense				$ 7,141,000	$ 10,362,000	$ 21,838,000	$ 19,943,000
ESPP
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Maximum number of common stock that may be issued (shares)								875,000	375,000
Eliminated increase to the number of shares authorized for issuance that was previously automatically added annually								31,250
ESPP \| Common Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares available for grant (shares)			524,962	524,962		524,962
Restricted stock units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vested (shares)						220,000
PSU's
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vested (shares)	128,000
Stock-based compensation expense						$ 1,400,000
Underwritten public offering
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares issued in public offering (in shares)		9,798,000
Price per share (in usd per share)		$ 23.50
Proceeds realized from offering		$ 221,700,000
Option to purchase additional shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares issued in public offering (in shares)		1,278,000