Adjusted LIBOR rate

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Debt instrument repayment term.

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Unsecured Revolving Credit Facility

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

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

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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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Amount of the required periodic payments including both interest and principal payments.

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Amount of the required periodic payments applied to principal.

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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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Amount of cash paid for interest, including, but not limited to, capitalized interest and payment to settle zero-coupon bond attributable to accreted interest of debt discount and debt instrument with insignificant coupon interest rate in relation to effective interest rate of borrowing attributable to accreted interest of debt discount; classified as operating and investing activities.

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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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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 long-term debt payable, sinking fund requirement, and other securities issued that are redeemable by holder at fixed or determinable price and date, maturing after fifth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of long-term debt payable, sinking fund requirement, and other securities issued that are redeemable by holder at fixed or determinable price and date, maturing in next fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of long-term debt payable, sinking fund requirement, and other securities issued that are redeemable by holder at fixed or determinable price and date, maturing in fifth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of long-term debt payable, sinking fund requirement, and other securities issued that are redeemable by holder at fixed or determinable price and date, maturing in fourth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of long-term debt payable, sinking fund requirement, and other securities issued that are redeemable by holder at fixed or determinable price and date, maturing in third fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of long-term debt payable, sinking fund requirement, and other securities issued that are redeemable by holder at fixed or determinable price and date, maturing in second fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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The cash inflow during the period from additional borrowings in aggregate debt. Includes proceeds from short-term and long-term debt.

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Including the current and noncurrent portions, carrying value as of the balance sheet date of Notes with the highest claim on the assets of the issuer in case of bankruptcy or liquidation (with maturities initially due after one year or beyond the operating cycle if longer). Senior note holders are paid off in full before any payments are made to junior note holders.

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Carrying value as of the balance sheet date of uncollateralized debt obligation (with maturities initially due after one year or beyond the operating cycle if longer), excluding current portion.

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Write-off of amounts previously capitalized as debt issuance cost in an extinguishment of debt.

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Long-Term Debt - Additional Information (Details) - USD ($)		3 Months Ended		12 Months Ended
	Dec. 21, 2018	Dec. 31, 2018	Jun. 30, 2017	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	Sep. 24, 2020	Mar. 31, 2019	Mar. 11, 2019	Jun. 28, 2017	Sep. 18, 2014	Apr. 17, 2014
Debt Instrument [Line Items]
Unsecured revolving credit facility				$ 0	$ 100,000,000.0					$ 400,000,000.0		$ 800,000,000.0
Debt instrument, periodic payment, principal					330,000,000.0
Proceeds from issuance of debt		$ 2,800,000
Debt issuance costs										$ 1,600,000
Write off of deferred debt issuance cost			$ 200,000
Unsecured term loans				290,000,000.0
Outstanding debt balance				2,095,906,000	1,555,343,000
Debt instrument, periodic payment, principal	$ 250,000,000.0
Interest				52,400,000	58,300,000	$ 38,000,000.0
Long-term Debt, Maturities, Repayments of Principal in Next Twelve Months				70,000,000.0
Long-term Debt, Maturities, Repayments of Principal in Year Two				280,000,000.0
Long-term Debt, Maturities, Repayments of Principal in Year Three				210,000,000.0
Long-term Debt, Maturities, Repayments of Principal in Year Four				500,000,000.0
Long-term Debt, Maturities, Repayments of Principal in Year Five				350,000,000.0
Long-term Debt, Maturities, Repayments of Principal after Year Five				$ 700,000,000.0
Minimum
Debt Instrument [Line Items]
Debt instrument, variable interest rate				1.00%
Maximum
Debt Instrument [Line Items]
Debt instrument, variable interest rate				1.75%
Unsecured Senior Notes
Debt Instrument [Line Items]
Debt instrument, face amount											$ 500,000,000.0
Debt instrument interest rate stated percentage							2.375%		4.50%		4.20%
Outstanding debt balance				$ 500,000,000.0	$ 500,000,000.0		$ 200,000,000.0	$ 350,000,000.0
4.500% Senior Notes, Semi-Annual Interest Payments, Balloon Due 2029
Debt Instrument [Line Items]
Debt instrument interest rate stated percentage				4.50%	4.50%
Senior notes				$ 350,000,000.0	$ 350,000,000.0				$ 350,000,000.0
2.375% Senior Note due 2031, Semi-Annual Interest Payments, Balloon Due 2031
Debt Instrument [Line Items]
Debt instrument interest rate stated percentage				2.375%	2.375%
Senior notes				$ 700,000,000.0			$ 700,000,000.0
Term Loan
Debt Instrument [Line Items]
Debt instrument, periodic payment, principal		$ 67,500,000
Unsecured term loans	$ 300,000,000.0			$ 270,000,000.0	$ 285,000,000.0
Loan repayment term	5 years
Term Loan \| LIBOR
Debt Instrument [Line Items]
30-day Adjusted LIBOR Rate				0.188%
Term Loan \| Minimum
Debt Instrument [Line Items]
Unsecured term loans	$ 300,000,000.0
Term Loan \| Maximum
Debt Instrument [Line Items]
Unsecured term loans	$ 450,000,000.0
Revolving Credit Facility
Debt Instrument [Line Items]
Credit facility, outstanding amount											$ 475,000,000.0
Long-term Debt \| LIBOR
Debt Instrument [Line Items]
30-day Adjusted LIBOR Rate				0.188%