Common shares registered for resale in connection with convertible notes.

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The multiple of principal used in calculating the number of shares converted from the notes.

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Debt instrument, redemption period, stock price exceeds in percentage of conversion price.

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Amount of noncash expense included in interest expense to amortize debt discount and premium associated with the related debt instruments. Excludes amortization of financing costs. Alternate captions include noncash interest expense.

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Amount of amortization expense attributable to debt issuance costs.

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The number of shares issued in exchange for the original debt being converted in a noncash (or part noncash) transaction. "Part noncash" refers to that portion of the transaction not resulting in cash receipts or payments in the period.

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Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

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The price per share of the conversion feature embedded in the debt instrument.

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Date the debt agreement requires the first payment to be made, in CCYY-MM-DD format.

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Face (par) amount of debt instrument at time of issuance.

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Description of the frequency of periodic payments (monthly, quarterly, annual).

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Amount of increase (decrease) in debt instruments, classified as other.

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Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium.

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Contractual interest rate for funds borrowed, under the debt agreement.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Date when the debt instrument is scheduled to be fully repaid, in CCYY-MM-DD format.

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Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Amount, after accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

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Amount of the cost of borrowed funds accounted for as interest expense for debt.

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Represents the portion of interest incurred in the period on debt arrangements that was charged against earnings, excluding amortization of debt discount (premium) and financing costs.

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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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Interest paid other than in cash for example by issuing additional debt securities. As a noncash item, it is added to net income when calculating cash provided by or used in operations using the indirect method.

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The cash outflow paid to third parties in connection with debt origination, which will be amortized over the remaining maturity period of the associated long-term debt.

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The cash inflow from the issuance of a long-term debt instrument which can be exchanged for a specified amount of another security, typically the entity's common stock, at the option of the issuer or the holder.

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Number of shares issued during the period as a result of the conversion of convertible securities.

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Convertible Notes - Additional Information (Details) - USD ($)		1 Months Ended		3 Months Ended		6 Months Ended
	Jul. 29, 2011	May 31, 2021	Apr. 30, 2011	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Debt Instrument [Line Items]
Net proceeds from convertible note financing						$ 148,982,000
Amortization of debt discount						785,000	$ 645,000
Common Stock
Debt Instrument [Line Items]
Initial conversion price/rate		$ 15.276
Issuance of common stock on conversion of notes (in shares)		9,800,000		9,849,000
Notes
Debt Instrument [Line Items]
Convertible debt issuable in connection with private placement		$ 150,000,000.0
Net proceeds from convertible note financing		$ 149,000,000.0
Debt instrument, interest rate		1.50%
Debt instrument, maturity date		May 26, 2026
Debt instrument, frequency of periodic payment		semi-annually
Debt instrument, date of first required payment		Dec. 15, 2021
Initial conversion price/rate		$ 65.4620
Debt instrument conversion ratio multiple of principal		$ 1,000
Common shares registered for resale in connection with convertible notes		12,400,000
Debt issuance costs incurred						$ 1,000,000.0
Effective interest rate				1.60%		1.60%
Interest expense				$ 231,000		$ 231,000
Interest expense, debt, excluding amortization				212,000		212,000
Amortization of debt issuance costs				19,000		19,000
Carrying value of debt				149,000,000.0		149,000,000.0
Debt instrument, face amount				150,000,000.0		150,000,000.0
Debt issuance costs				1,000,000.0		1,000,000.0
Notes \| Redemption Between May 24, 2024 and May 24, 2025
Debt Instrument [Line Items]
Debt instrument, redemption period, stock price exceeds in percentage of conversion price		250.00%
Notes \| Redemption On or After May 24, 2025
Debt Instrument [Line Items]
Debt instrument, redemption period, stock price exceeds in percentage of conversion price		200.00%
Convertible Notes
Debt Instrument [Line Items]
Convertible debt issuable in connection with private placement			$ 4,500,000
Net proceeds from convertible note financing			$ 4,300,000
Debt instrument, interest rate			6.00%
Debt instrument, maturity date			May 02, 2021
Debt instrument conversion ratio multiple of principal			$ 1,000
Common shares registered for resale in connection with convertible notes	3,500,000
Interest expense, debt, excluding amortization				100,000	$ 100,000	200,000	200,000
Carrying value of debt		$ 0
Debt instrument, term			10 years
Paid-in-kind interest						200,000
Debt instrument, additional debt discount						200,000
Amortization of debt discount				$ 300,000	$ 300,000	$ 800,000	$ 600,000
Convertible Notes \| Common Stock
Debt Instrument [Line Items]
Debt instrument, number of shares issued for convertible notes			1,250