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

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition

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

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
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- 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.

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- 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
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Notes Payable - Issuance (Details) - USD ($)	1 Months Ended
Notes Payable - Issuance (Details) - USD ($)	May 31, 2018	Dec. 31, 2019	Dec. 31, 2018
Convertible senior notes, 0.25%, due 2023
Debt Instrument [Line Items]
Aggregate principal amount		$ 549,999,000	$ 550,000,000.0
Interest rate (as a percent)	0.25%
Net proceeds from the debt offering	$ 537,000,000.0
Convertible senior notes, 0.25%, due 2023 - over-allotment
Debt Instrument [Line Items]
Aggregate principal amount	$ 75,000,000.0