Loan and Security Agreement - Additional Information (Details)	1 Months Ended			12 Months Ended
	Sep. 30, 2020 USD ($)	Mar. 31, 2019 USD ($)	Nov. 30, 2016 USD ($) tranche	Dec. 31, 2020 USD ($)	Dec. 31, 2019 USD ($)	Dec. 31, 2018 USD ($)
Line Of Credit Facility [Line Items]
Loss on extinguishment of debt				$ (1,247,012)
Repayment of principal on term loan				21,660,000	$ 7,238,889	$ 3,333,333
Interest expense				2,362,083	1,362,500	751,670
Amortization of debt issuance costs				469,676	436,567	266,668
Amortization of debt discount				786,750	649,993	375,635
Warrants
Line Of Credit Facility [Line Items]
Amortization of debt discount				317,074	$ 213,426	$ 108,968
Term Loan 2020
Line Of Credit Facility [Line Items]
First advance used to repay previous debt	$ 21,700,000
Base interest rate	9.15%
Cash pay interest rate	1.00%
Cash pay interest multiplier	1.15
Final payment fee	$ 2,910,000
Percentage of final payment fee	4.85%
Loss on extinguishment of debt				$ 1,200,000
Term Loan 2020 | Prime Rate
Line Of Credit Facility [Line Items]
Interest rate basis	5.90%
Term Loan 2020 | Prepayment Occurs Prior to First Anniversary of Closing Date
Line Of Credit Facility [Line Items]
Maximum loan amount	$ 225,000,000.0
Percentage of prepayment penalty	2.00%
Term Loan 2020 | Outstanding principle and advances under the loans agreement exceeds 55 million
Line Of Credit Facility [Line Items]
Minimum cash to be maintain as a first priority security interest	$ 15,000,000.0
Period of unpaid invoices amount maintain as security	180 days
Term Loan 2020 | Outstanding principle and advances under the loans agreement exceeds 55 million | Minimum
Line Of Credit Facility [Line Items]
Outstanding amount	$ 55,000,000.0
Term Loan 2020 | Outstanding principle and advances under the loans agreement exceeds 65 million
Line Of Credit Facility [Line Items]
Minimum amount of market capital to be maintained	$ 2,000,000,000.0
Minimum percentage of cash to be maintained as a security following market capitalization condition	65.00%
Minimum percentage of cash to be maintained as a security	100.00%
Term Loan 2020 | Outstanding principle and advances under the loans agreement exceeds 65 million | AXS-05 and AXS-07
Line Of Credit Facility [Line Items]
Minimum product revenue percent	60.00%
Term Loan 2020 | Outstanding principle and advances under the loans agreement exceeds 65 million | Minimum
Line Of Credit Facility [Line Items]
Outstanding amount	$ 65,000,000.0
Term Loan 2020 | Prepayment Occurs on or After First Anniversary and Prior to Second Anniversary of the Closing Date
Line Of Credit Facility [Line Items]
Percentage of prepayment penalty	1.50%
Term Loan 2020 | Prepayment Occurs on or After Second Anniversary and Prior to Third Anniversary of Closing Date
Line Of Credit Facility [Line Items]
Percentage of prepayment penalty	1.00%
Term loan 2020 tranche one
Line Of Credit Facility [Line Items]
Maximum loan amount	$ 60,000,000.0
Proceeds from debt	50,000,000.0
Remaining credit facility to be drawn	10,000,000.0
Term loan 2020 tranche two
Line Of Credit Facility [Line Items]
Maximum loan amount	$ 35,000,000.0
Period to achieve first milestone	181 days
Term loan 2020 tranche three
Line Of Credit Facility [Line Items]
Maximum loan amount	$ 20,000,000.0
Period to achieve second milestone	181 days
Term loan 2020 tranche four
Line Of Credit Facility [Line Items]
Maximum loan amount	$ 60,000,000.0
Term loan 2020 tranche five
Line Of Credit Facility [Line Items]
Maximum loan amount	$ 50,000,000.0
Original Term Loan 2016
Line Of Credit Facility [Line Items]
Maximum loan amount			$ 20,000,000.0
Number of loan tranches | tranche			3
Term Loan 2016, Tranche One
Line Of Credit Facility [Line Items]
Maximum loan amount			$ 10,000,000.0
Term Loan 2016, Tranche Two and Three
Line Of Credit Facility [Line Items]
Maximum loan amount			10,000,000.0
Amended Term Loan 2016
Line Of Credit Facility [Line Items]
Remaining credit facility to be drawn			$ 4,000,000.0
2019 Term Loan
Line Of Credit Facility [Line Items]
Maximum loan amount		$ 24,000,000.0
Interest rate basis		7.50%
Repayment of principal on term loan		$ 1,260,000
Term Loan 2019, Tranche One
Line Of Credit Facility [Line Items]
Final payment fee		850,000
Loan amount		20,000,000.0
Repayment of principal on term loan		5,600,000
Term Loan 2019, Tranche Two
Line Of Credit Facility [Line Items]
Remaining credit facility to be drawn		$ 4,000,000.0