Debt - Summary of Senior Unsecured Notes (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2020	Dec. 31, 2019
Debt Instrument [Line Items]
Total Senior Unsecured Notes	$ 2,562,320	$ 2,179,838
Weighted Average
Debt Instrument [Line Items]
Stated Interest Rate	3.59%
Senior Notes
Debt Instrument [Line Items]
Total Senior Unsecured Notes	$ 1,500,000	1,500,000
Senior Notes \| Weighted Average
Debt Instrument [Line Items]
Stated Interest Rate	3.73%
2026 Senior Notes \| Senior Notes
Debt Instrument [Line Items]
Maturity Date	Sep. 15, 2026
Stated Interest Rate	4.45%
Total Senior Unsecured Notes	$ 300,000	300,000
2027 Senior Notes \| Senior Notes
Debt Instrument [Line Items]
Maturity Date	Jan. 15, 2027
Stated Interest Rate	3.20%
Total Senior Unsecured Notes	$ 300,000	300,000
2029 Senior Notes \| Senior Notes
Debt Instrument [Line Items]
Maturity Date	Jul. 15, 2029
Stated Interest Rate	4.00%
Total Senior Unsecured Notes	$ 400,000	400,000
2030 Senior Notes \| Senior Notes
Debt Instrument [Line Items]
Maturity Date	Jan. 15, 2030
Stated Interest Rate	3.40%
Total Senior Unsecured Notes	$ 500,000	$ 500,000

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.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 4
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
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Reference 3: 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

Date when the debt instrument is scheduled to be fully repaid, in CCYY-MM-DD format.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.22(a)(2))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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-Publisher FASB
-Name Accounting Standards Codification
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