Stockholders' Equity (Details Textual) - USD ($) $ / shares in Units, $ in Thousands					6 Months Ended	66 Months Ended	90 Months Ended
	Feb. 16, 2021	Jun. 30, 2015	Dec. 31, 2013	Nov. 14, 2013	Jun. 30, 2021	Jun. 30, 2021	Jun. 30, 2021
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted (in shares)					0
Exercises in period, intrinsic value					$ 4,308
Compensation cost not yet recognized, options					$ 653	$ 653	$ 653
Public Stock Offering
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Sale of stock, number of shares issued in transaction	7,961,538
Sale of stock, price per share (in dollars per share)	$ 65.00
Sale of stock, consideration received on transaction	$ 500,034
Payments of stock issuance costs	$ 17,466
Public Stock Offering - Additional Optional Shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Sale of stock, number of shares issued in transaction	1,038,459
Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation cost not yet recognized, period for recognition					2 years 3 months 3 days
Restricted Stock Units (RSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation cost not yet recognized, period for recognition					2 years 6 months 7 days
Compensation cost not yet recognized, non-option					$ 242,624	$ 242,624	$ 242,624
The 2005 Stock Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock, capital shares reserved for future issuance (in shares)			14,139,957
Granted (in shares)							0
Shares available for grant (in shares)					0	0	0
The 2005 Stock Plan | Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period (in years)			4 years
The 2013 Omnibus Equity Award Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock, capital shares reserved for future issuance (in shares)				5,713,899
Vesting period (in years)				4 years
Percentage of outstanding stock reserved for grant				4.00%
Percentage of outstanding stock maximum				5.00%
Capital shares reserved for future issuance, annual increase, maximum (in shares)					20,388,450	20,388,450	20,388,450
2015 ESPP
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Maximum employee subscription rate		15.00%
Purchase price of common stock, percent		85.00%
Number of shares authorized (in shares)		1,500,000
Percent of shares increase, employee stock purchase plan		1.00%
Common stock availability threshold, Employee Stock Purchase Plan		2.00%
Shares increase threshold, employee stock purchase plan (in shares)		1,200,000
Number of additional shares authorized (in shares)						2,539,854