Debt instrument commencement of interest date.

No definition available.

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- Definition

Debt instrument convertible conversion rate principal amount.

+ References

No definition available.

+ Details

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Balance Type:	credit
Period Type:	instant

- Definition

Line Of Credit Facility Increase In Borrowing Capacity

+ References

No definition available.

+ Details

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Balance Type:	credit
Period Type:	instant

- Definition

Option to purchase additional principal amount of notes to underwriters.

+ References

No definition available.

+ Details

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- Definition

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.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 50
-Paragraph 5
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Period Type:	duration

- Definition

The carrying amount of the equity component of convertible debt which may be settled in cash upon conversion.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 4
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=120520924&loc=SL6031897-161870

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Balance Type:	credit
Period Type:	instant

- Definition

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

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-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 5
-Subparagraph (b)
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Period Type:	instant

- Definition

The amount by which the convertible debt's if-converted value exceeds its principle amount at the balance sheet date, regardless of whether the instrument is currently convertible. This element applies to public companies only.

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-SubTopic 20
-Section 50
-Paragraph 5
-Subparagraph (c)
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- Definition

Description of the conversion terms of a debt instrument which may include the conversion ratio (including all potential conversion ratios if contingently adjustable), type of debt or equity security into which the debt is convertible, the dollars of debt or the number of shares into which the instrument is convertible (or potentially convertible into), the conversion period, any contingencies associated with the conversion terms, and the existence and amount of a beneficial conversion feature.

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- Definition

Threshold period of specified consecutive trading days within which common stock price to conversion price of convertible debt instrument must exceed threshold percentage for specified number of trading days to trigger conversion feature.

+ References

No definition available.

+ Details

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- Definition

Minimum percentage of common stock price to conversion price of convertible debt instruments to determine eligibility of conversion.

+ References

No definition available.

+ Details

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- Definition

Threshold number of specified trading days that common stock price to conversion price of convertible debt instruments must exceed threshold percentage within a specified consecutive trading period to trigger conversion feature.

+ References

No definition available.

+ Details

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- Definition

Identification of the lender and information about a contractual promise to repay a short-term or long-term obligation, which includes borrowings under lines of credit, notes payable, commercial paper, bonds payable, debentures, and other contractual obligations for payment. This may include rationale for entering into the arrangement, significant terms of the arrangement, which may include amount, repayment terms, priority, collateral required, debt covenants, borrowing capacity, call features, participation rights, conversion provisions, sinking-fund requirements, voting rights, basis for conversion if convertible and remarketing provisions. The description may be provided for individual debt instruments, rational groupings of debt instruments, or by debt in total.

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- Definition

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

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-Name Accounting Standards Codification
-Topic 835
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-Paragraph 2
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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

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

+ References

+ Details

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- Definition

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

+ References

+ Details

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Balance Type:	na
Period Type:	instant

- Definition

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.

+ References

No definition available.

+ Details

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.22(a)(2))
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-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (bbb)(2)
-URI http://asc.fasb.org/extlink&oid=117815213&loc=d3e19207-110258

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- Definition

The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

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Balance Type:	credit
Period Type:	instant

- Definition

Amount of current borrowing capacity under the credit facility considering any current restrictions on the amount that could be borrowed (for example, borrowings may be limited by the amount of current assets), but without considering any amounts currently outstanding under the facility.

+ References

+ Details

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Period Type:	instant

- Definition

Date the credit facility terminates, in CCYY-MM-DD format.

+ References

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- Definition

Amount of borrowing capacity currently available under the credit facility (current borrowing capacity less the amount of borrowings outstanding).

+ References

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The cash inflow from additional borrowings, net of cash paid to third parties in connection with debt origination.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 14
-Subparagraph (b)
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Period Type:	duration

- Details

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- Details

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- Details

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Debt - Additional Information (Detail)	1 Months Ended	6 Months Ended
Debt - Additional Information (Detail)	Jun. 30, 2019 USD ($) $ / shares shares	Jun. 30, 2021 USD ($) d	Dec. 31, 2020 USD ($)
Convertible Senior Notes Due in 2024 [Member]
Debt Instrument [Line Items]
Debt instrument, aggregate principal amount	$ 230,000,000.0
Debt instrument interest rate	0.25%
Additional principal amount of notes to underwriters	$ 30,000,000.0
Net proceeds from issuance of costs	$ 221,900,000
Debt instrument frequency of periodic payment		semi-annually
Interest payment commencement date	Dec. 01, 2019
Debt instrument maturity date	Jun. 01, 2024
Debt instrument, description		The Convertible Notes bear interest at a rate of 0.25% per year, payable semi-annually in arrears on June 1 and December 1 of each year, commencing December 1, 2019.
Debt instrument, convertible, terms of conversion feature		The Convertible Notes have an initial conversion rate of 21.5049 shares of the Company's Class A common stock per $1,000 principal amount of Convertible Notes, which is equivalent to an initial conversion price of approximately $46.50 per share of its Class A common stock.
Debt instrument, convertible, “if-converted value” in excess of the principal amount		$ 111,100,000
Net carrying value of equity component of convertible notes		$ 50,000,000.0	$ 50,000,000.0
Convertible Senior Notes Due in 2024 [Member] \| Class A Common Stock [Member]
Debt Instrument [Line Items]
Debt conversion, converted instrument, shares issued \| shares	21.5049
Debt instrument conversion rate principal amount of notes	$ 1,000
Debt instrument convertible initial conversion price per share of common stock \| $ / shares	$ 46.50
Convertible Senior Notes Due in 2024 [Member] \| Class A Common Stock [Member] \| Convertible Notes, Holders Conversion Rights, Circumstances 1 [Member]
Debt Instrument [Line Items]
Debt instrument, convertible, consecutive trading days \| d		30
Convertible Senior Notes Due in 2024 [Member] \| Class A Common Stock [Member] \| Convertible Notes, Holders Conversion Rights, Circumstances 1 [Member] \| Minimum [Member]
Debt Instrument [Line Items]
Debt instrument, convertible, trading days \| d		20
Debt instrument, convertible, threshold percentage of conversion price		130.00%
Twenty Nineteen Credit Agreement
Debt Instrument [Line Items]
Maturity date		Dec. 15, 2023
Credit facility		$ 150,000,000.0
Increase in line of credit borrowing capacity		50,000,000.0
Secured Credit Agreement [Member]
Debt Instrument [Line Items]
Loan outstanding		0
Amount available for future borrowing		$ 150,000,000.0