Debt - Outstanding Debt Including Finance Leases (Details) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Debt Instrument [Line Items]
Weighted average effective interest rate (as a percent)	3.09%
Total debt and lease obligations	$ 1,667,862	$ 1,463,904
Less net debt issuance costs	(9,474)	(10,839)
Total outstanding debt, net	1,658,388	1,453,065
Lenexa Mortgage
Debt Instrument [Line Items]
Outstanding debt	$ 1,700
Unsecured Credit Facility, Revolving Credit Facility, Matures on December 17, 2023
Debt Instrument [Line Items]
Weighted average effective interest rate (as a percent)	1.38%
Outstanding debt	$ 522,951	317,028
Unsecured Credit Facility, Term Loan A, Matures on December 17, 2024
Debt Instrument [Line Items]
Weighted average effective interest rate (as a percent)	3.26%
Outstanding debt	$ 225,000	225,000
Unsecured Credit Facility, Term Loan B, Matures on April 27 2025
Debt Instrument [Line Items]
Weighted average effective interest rate (as a percent)	3.30%
Outstanding debt	$ 225,000	225,000
Unsecured Credit Facility, Term Loan C, Matures on October 18 2026
Debt Instrument [Line Items]
Weighted average effective interest rate (as a percent)	3.46%
Outstanding debt	$ 250,000	250,000
Senior Notes
Debt Instrument [Line Items]
Weighted average effective interest rate (as a percent)	4.75%
Outstanding debt	$ 400,000	400,000
Lenexa Mortgage
Debt Instrument [Line Items]
Weighted average effective interest rate (as a percent)	4.10%
Outstanding debt	$ 1,689	1,736
Finance Leases
Debt Instrument [Line Items]
Weighted average effective interest rate (as a percent)	4.36%
Outstanding debt	$ 43,222	$ 45,140

Amount of short-term and long-term debt and lease obligation.

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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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Amount, after accumulated amortization, of debt discount (premium).

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Weighted average interest rate of debt outstanding.

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The fair value amount of long-term debt whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission.

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