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Right to particiapte in equity financing.

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The total amount of long-term liability charges that are being deferred beyond one year.

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The maximum amount of borrowing capacity under a line of credit that is available as of the balance sheet date for a specific purpose other than for financing goods acquired for inventory or imminent delivery to a customer.

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The fee, expressed as a percentage of the line of credit facility, for the line of credit facility regardless of whether the facility has been used.

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The effective interest rate at the end of the reporting period.

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Description of the interest rate for the amounts borrowed under the credit facility, including the terms and the method for determining the interest rate (for example, fixed or variable, LIBOR plus a percentage, increasing rate, timing of interest rate resets, remarketing provisions).

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Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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Amount of cash inflow from contractual arrangement with the lender, including but not limited to, letter of credit, standby letter of credit and revolving credit arrangements.

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Long-term Debt - Additional Information (Detail)				6 Months Ended
Long-term Debt - Additional Information (Detail)	Mar. 31, 2020	Jan. 08, 2020 USD ($) Tranche	Dec. 28, 2017 USD ($)	Jun. 30, 2020 USD ($)	Dec. 31, 2019 USD ($)
Debt Instrument [Line Items]
Line of credit facility, advance amount				$ 20,000,000.0
Line of credit facility, interest rate			8.05%
Borrowings outstanding				24,252,000
Discount on borrowings				$ 748,000
Hercules Capital Inc [Member]
Debt Instrument [Line Items]
Purchase of common stock		$ 1,000,000.0
Tranche One [Member]
Debt Instrument [Line Items]
Line of credit facility, interest rate		8.50%
Term Loan [Member]
Debt Instrument [Line Items]
Line of credit facility, maximum borrowing capacity			$ 50,000,000.0
Line of credit facility, interest rate				8.05%
Line of credit facility, interest rate description				As of June 30, 2020, the Company had borrowed $20.0 million under the Credit Facility, with an interest rate of 8.05% per annum and the remaining available amount had expired. Advances under the Credit Facility bear an interest rate equal to the greater of either (i) 8.05% plus the prime rate as reported from time to time in The Wall Street Journal (the Prime Rate) minus 4.75%, and (ii) 8.05%. The Company will make interest-only payments through July 1, 2021, and will then repay the principal balance and interest on the advances in equal monthly installments and continuing through December 1, 2022. The Company will pay an end of term charge of $1.3 million.
Line of credit facility, maturity date				Dec. 01, 2022
Payment of end term charge				$ 1,300,000
Loan commitment charge, percentage		1.00%
Borrowings outstanding				24,252,000	$ 19,786,000
Discount on borrowings				$ 748,000	$ 214,000
Term Loan [Member] \| Minimum [Member]
Debt Instrument [Line Items]
Loan commitment charge		$ 162,500
Aggregate proceeds to be received from equity offering		30,000,000.0
Term Loan [Member] \| Maximum [Member] \| Hercules Capital Inc [Member]
Debt Instrument [Line Items]
Amount of participation in equity financing		3,000,000.0
Term Loan [Member] \| Wall Street Journal Prime [Member]
Debt Instrument [Line Items]
Line of credit facility, interest rate				4.75%
Term Loan Restated [Member]
Debt Instrument [Line Items]
Line of credit facility, maximum borrowing capacity		$ 100,000,000.0
Line of credit facility, interest rate description				In addition, the Company may prepay advances under the Amended Loan Agreement, in whole or in part, at any time, subject to a prepayment charge that ranges from 1.0% to 2.0%, depending on the timing of the prepayment. The Amended Loan Agreement is secured by substantially all of the Company’s assets, excluding intellectual property. The Amended Loan Agreement also includes customary loan covenants, with which the Company was in compliance for all periods presented.
Number of tranches \| Tranche		3
Term Loan Restated [Member] \| Minimum [Member]
Debt Instrument [Line Items]
Loan commitment charge		$ 520,000
Term Loan Restated [Member] \| Tranche One [Member]
Debt Instrument [Line Items]
Line of credit facility, advance amount				$ 5,000,000.0
Line of credit facility, interest rate	8.50%
Line of credit facility, interest rate description				Under the Restated Credit Facility, the Company had borrowed $5.0 million from the first tranche with an interest rate of 8.50% per annum as of June 30, 2020. Advances under the Restated Credit Facility bear an initial interest rate equals to the greater of either (i) 8.50% plus the Prime Rate minus 5.25%, and (ii) 8.50%, which may be reduced upon the Company achieving certain cumulative net avacopan revenue levels. For advances under the Restated Credit Facility, the Company will make interest only payments through September 1, 2022 and will then repay the principal balance and interest on the advances in equal monthly installments through February 1, 2024. Upon satisfaction of certain conditions, the interest-only payment period and the principal balance repayment period may be extended. In addition, the Company will pay an end of term charge of 7.15% of the aggregate amount of the advances under the Restated Credit Facility.
Line of credit facility, maturity date				Feb. 01, 2024
End of term charge advances, percentage				7.15%
Term Loan Restated [Member] \| Wall Street Journal Prime [Member] \| Tranche One [Member]
Debt Instrument [Line Items]
Line of credit facility, interest rate				5.25%
Through December 15, 2020 [Member] \| Tranche One [Member]
Debt Instrument [Line Items]
Line of credit facility, maximum borrowing capacity		40,000,000.0
Through December 15, 2020 [Member] \| Tranche One [Member] \| Avacopan New Drug Application
Debt Instrument [Line Items]
Line of credit facility, capacity available for specific purpose other than for trade purchases		20,000,000.0
Through December 15, 2021 [Member] \| Tranche Two [Member] \| Avacopan New Drug Application
Debt Instrument [Line Items]
Restated credit facility, maximum borrowing capacity		30,000,000.0
Through December 15, 2022 [Member] \| Tranche Three [Member]
Debt Instrument [Line Items]
Line of credit facility, maximum borrowing capacity		$ 30,000,000.0