Debt instrument, premium redemption price, percentage.

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Line of credit facility additional borrowing capacity.

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Percentage points added to the reference rate to compute the variable rate on the debt instrument.

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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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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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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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Description of the payment terms of the debt instrument (for example, whether periodic payments include principal and frequency of payments) and discussion about any contingencies associated with the payment.

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Amount of the required periodic payments applied to interest.

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Description of debt redemption features under terms of the debt agreement.

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Start date of debt instrument redemption period, in CCYY-MM-DD format.

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Percentage price of original principal amount of debt at which debt can be redeemed by the issuer.

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Percentage of principal amount of debt redeemed.

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

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

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Gross amount of debt extinguished.

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No definition available.

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

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

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

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The fee, expressed as a percentage of the line of credit facility, for available but unused credit capacity under the credit 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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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 additional borrowings, net of cash paid to third parties in connection with debt origination.

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The cash outflow during the period from the repayment of aggregate short-term and long-term debt. Excludes payment of capital lease obligations.

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Amount of cash outflow for payment of an obligation from a lender, including but not limited to, letter of credit, standby letter of credit and revolving credit arrangements.

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The remaining balance of debt issuance expenses that were capitalized and are being amortized against income over the lives of the respective bond issues. This does not include the amounts capitalized as part of the cost of the utility plant or asset.

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Debt - Additional Information (Detail) - USD ($)			1 Months Ended	12 Months Ended
Debt - Additional Information (Detail) - USD ($)	Jun. 10, 2019	Feb. 06, 2019	Dec. 31, 2019	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Debt Instrument [Line Items]
Repayment of outstanding term and revolving loan borrowings				$ 342,313,000	$ 53,906,000	$ 25,781,000
Long-term debt			$ 500,000,000	500,000,000	342,312,000
Debt issuance costs				9,136,000		1,979,000
Unamortized deferred debt issuance costs			$ 6,991,000	6,991,000	514,000
Unamortized debt issuance expense					1,900,000
Interest expense				24,300,000	$ 7,500,000	$ 2,100,000
Write-off of unamortized debt issuance costs upon extinguishment of term loan				$ 1,900,000
Effective interest rate			5.18%	5.18%	3.82%	3.00%
Credit Agreement
Debt Instrument [Line Items]
Credit facility, additional borrowing capacity			$ 250,000,000	$ 250,000,000
Credit facility, expiration date		Feb. 05, 2024
Credit facility, borrowings interest rate description				borrowings bear interest, at the Company’s option, based on LIBOR or an alternate base rate plus a margin.
Repayment of outstanding term and revolving loan borrowings				$ 342,300,000
Long-term debt			0	$ 0
Credit Agreement \| Minimum
Debt Instrument [Line Items]
Credit facility, commitment fee on undrawn portion available		0.15%
Credit Agreement \| Minimum \| LIBOR
Debt Instrument [Line Items]
Credit facility, variable rate		1.125%
Credit Agreement \| Minimum \| Base Rate
Debt Instrument [Line Items]
Credit facility, variable rate		0.125%
Credit Agreement \| Maximum
Debt Instrument [Line Items]
Credit facility, commitment fee on undrawn portion available		0.275%
Credit Agreement \| Maximum \| LIBOR
Debt Instrument [Line Items]
Credit facility, variable rate		1.75%
Credit Agreement \| Maximum \| Base Rate
Debt Instrument [Line Items]
Credit facility, variable rate		0.75%
Prior Credit Facility
Debt Instrument [Line Items]
Credit facility, maximum borrowing capacity		$ 350,000,000
Credit facility, expiration date		Oct. 09, 2022
Senior Notes
Debt Instrument [Line Items]
Debt instrument, redemption, description				The Company has the option to redeem all or a portion of the Senior Notes at any time on or after July 1, 2022 by paying 100.0% of the principal amount of the Senior Notes plus a declining premium, plus accrued and unpaid interest to (but excluding) the redemption date. The premium declines from 2.750% during the twelve months on and after July 1, 2022, to 1.833% during the twelve months on and after July 1, 2023, to 0.917% during the twelve months on and after July 1, 2024, to zero on and after July 1, 2025. The Company may also redeem all or any portion of the Senior Notes at any time prior to July 1, 2022, at a price equal to 100.0% of the aggregate principal amount thereof plus a make-whole premium set forth in the Indenture and accrued and unpaid interest, if any. In addition, before July 1, 2022, the Company may redeem up to 40% of the aggregate principal amount of the Senior Notes with the net proceeds of certain equity offerings at a redemption price of 105.5% of the principal amount plus accrued and unpaid interest, if any, provided that certain conditions are met
Debt instrument, redemption period, start date	Jul. 01, 2022
Long-term debt			500,000,000	$ 500,000,000
Senior Notes \| Minimum
Debt Instrument [Line Items]
Debt instrument, redemption price, percentage	100.00%
Senior Notes \| Redeemable Senior Notes After July 1, 2022
Debt Instrument [Line Items]
Debt instrument, redemption period, start date				Jul. 01, 2022
Debt instrument, premium redemption price, percentage				2.75%
Senior Notes \| Redeemable Senior Notes After July 1, 2023
Debt Instrument [Line Items]
Debt instrument, redemption period, start date				Jul. 01, 2023
Debt instrument, premium redemption price, percentage				1.833%
Senior Notes \| Redeemable Senior Notes After July 1, 2024
Debt Instrument [Line Items]
Debt instrument, redemption period, start date				Jul. 01, 2024
Debt instrument, premium redemption price, percentage				0.917%
Senior Notes \| Redeemable Senior Notes After July 1, 2025
Debt Instrument [Line Items]
Debt instrument, redemption period, start date				Jul. 01, 2025
Debt instrument, premium redemption price, percentage				0.00%
Senior Notes \| Redeemable Senior Notes Before July 1, 2022 Following Equity Offering
Debt Instrument [Line Items]
Debt instrument, redemption price, percentage				105.50%
Debt instrument percentage of principal amount may be redeemed				40.00%
Senior Notes \| Change of Control Event
Debt Instrument [Line Items]
Debt instrument, redemption price, percentage				101.00%
Senior Notes \| Grubhub Holdings Inc.
Debt Instrument [Line Items]
Long-term debt	$ 500,000,000.0
Debt instrument, interest rate	5.50%
Debt instrument, payment terms				Interest is payable on the Senior Notes semi-annually on January and July of each year, beginning on January 1, 2020
Debt instrument, first interest payment			15,400
Debt instrument, maturity date	Jul. 01, 2027
Net proceeds from sale of notes receivable	$ 494,400,000
Term Loans \| Credit Agreement
Debt Instrument [Line Items]
Prepay and extinguish of existing credit facility	323,000,000.0
Revolving Loans
Debt Instrument [Line Items]
Long-term debt					$ 222,000,000
Revolving Loans \| Credit Agreement
Debt Instrument [Line Items]
Payment of outstanding revolving loan under existing credit facility	17,300,000
Credit facility, maximum borrowing capacity		$ 225,000,000	225,000,000	$ 225,000,000
Credit facility, available borrowing capacity			219,500,000	219,500,000
Unamortized debt issuance expense			$ 1,100,000	$ 1,100,000
Term Loans \| Credit Agreement
Debt Instrument [Line Items]
Long-term debt		$ 325,000,000
Debt extinguishment amount	$ 325,000,000