Condensed Consolidated Statements of Cash Flows (unaudited) - USD ($)	9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017
Cash flows from operating activities:
Net loss	$ (25,392,600)	$ (19,321,180)
Adjustments to reconcile net loss to net cash used in operating activities:
Amortization of debt discount	13,473	13,473
Change in fair value of preferred unit warrant liability	193,779	(4,338)
Depreciation and amortization	483,052	246,367
Net accretion of bond discounts/premiums	213,190	312,561
Non-cash compensation	6,189,011	162,901
Changes in operating assets and liabilities:
Account receivable	25,000,000	0
Other receivable	(1,138,426)	887,835
Prepaid expenses and other current assets	(2,565,154)	22,940
Accounts payable	704,233	(648,028)
Accrued expenses	319,657	289,802
Deferred revenue	(7,883,755)	(5,006,582)
Net cash used in operating activities	(3,863,540)	(23,044,249)
Cash flows from investing activities:
Purchase of marketable securities	(114,393,545)	0
Maturities of marketable securities	38,799,000	12,033,000
Sales of marketable securities	0	9,077,435
Purchase of property, equipment and leasehold improvements	(2,209,112)	(577,859)
Net cash provided by (used in) investing activities	(77,803,657)	20,532,576
Cash flows from financing activities:
Repayments of long term debt	(129,191)	(119,885)
Proceeds from long term debt	2,000,000	0
Proceeds from sale of redeemable convertible preferred units	55,000,001	0
Proceeds from exercise of redeemable convertible preferred warrant	75,000	0
Net cash provided by (used in) financing activities	56,945,810	(119,885)
Net decrease in cash and cash equivalents	(24,721,387)	(2,631,558)
Cash and cash equivalents, beginning of the period	30,912,391	5,088,548
Cash and cash equivalents, end of the period	6,191,004	2,456,990
Supplemental disclosure of cash flow information:
Purchases of property, equipment and leasehold improvements unpaid at period end	322,301	0
Deferred offering costs included in accrued expenses	663,252	0
Cash paid for interest	19,331	25,433
Change in fair value of redeemable convertible preferred stock/units	$ (198,366,756)	$ 0