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

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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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Notes Payable - Issuance (Details) - USD ($)	1 Months Ended
Notes Payable - Issuance (Details) - USD ($)	Mar. 31, 2021	Jun. 30, 2021	Dec. 31, 2020
Senior Notes
Debt Instrument [Line Items]
Principal	$ 1,000,000,000.0
Net proceeds from the debt offering	985,100,000
Debt issuance costs, gross	2,400,000
Senior Notes 3.625 Percent Due 2029
Debt Instrument [Line Items]
Principal	$ 500,000,000.0	$ 500,000,000	$ 0
Interest rate (as a percent)	3.625%
Senior Notes 3.875 Percent Due 2031
Debt Instrument [Line Items]
Principal	$ 500,000,000.0	500,000,000	0
Interest rate (as a percent)	3.875%
Convertible senior notes due 2023
Debt Instrument [Line Items]
Principal		$ 0	$ 343,702,000