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Borrowings - Summary of Outstanding Debt (Details) - USD ($) $ in Thousands | 9 Months Ended |
--- | --- | ---
Sep. 30, 2019 | Dec. 31, 2018
Debt Instrument [Line Items] |  |
Unsecured Debt | $ 3,830,708 | $ 4,053,302
Total Outstanding Debt | $ 4,476,114 |
Debt Instrument, Interest Rate, Effective Percentage | 3.80% |
Unsecured Debt [Member] |  |
Debt Instrument [Line Items] |  |
Total Outstanding Debt | $ 3,830,708 |
Debt Instrument, Interest Rate, Effective Percentage | 3.70% |
Unsecured Debt [Member] | Fixed Rate Debt Senior Notes [Member] |  |
Debt Instrument [Line Items] |  |
Debt Instrument, Face Amount | $ 3,192,000 |
Debt Instrument, Interest Rate, Effective Percentage | 3.90% |
Contract Maturity | Mar. 01, 2026 |
Unsecured Debt [Member] | Commercial Paper Notes [Member] | Variable Rate Commercial Paper Program [Member] |  |
Debt Instrument [Line Items] |  |
Unsecured Debt | $ 200,000 |
Debt Instrument, Interest Rate, Effective Percentage | 2.30% |
Contract Maturity | Oct. 11, 2019 |
Unsecured Debt [Member] | Term Loan [Member] |  |
Debt Instrument [Line Items] |  |
Debt Instrument, Face Amount | $ 300,000 |
Debt Instrument, Interest Rate, Effective Percentage | 2.30% |
Contract Maturity | Mar. 01, 2022 |
Unsecured Debt [Member] | Variable Rate Debt [Member] |  |
Debt Instrument [Line Items] |  |
Unsecured Debt | $ 150,000 |
Debt Instrument, Interest Rate, Effective Percentage | 3.10% |
Contract Maturity | Feb. 26, 2021 |
Unsecured Debt [Member] | $1 Billion Unsecured Revolving Credit Facility [Member] | Fair Market Value Adjustment and Debt Issuance Cost [Member] |  |
Debt Instrument [Line Items] |  |
Debt Instrument, Face Amount | $ (11,292) |
Secured Debt [Member] |  |
Debt Instrument [Line Items] |  |
Total Outstanding Debt | $ 645,406 |
Debt Instrument, Interest Rate, Effective Percentage | 4.60% |
Secured Debt [Member] | Fixed Rate Debt Senior Notes [Member] |  |
Debt Instrument [Line Items] |  |
SEC Schedule, 12-29, Real Estate Companies, Investment in Mortgage Loans on Real Estate | $ 648,801 |
Debt Instrument, Interest Rate, Effective Percentage | 4.60% |
Contract Maturity | Oct. 03, 2036 |
Secured Debt [Member] | Fair Market Value Adjustment and Debt Issuance Cost [Member] |  |
Debt Instrument [Line Items] |  |
Line of Credit Facility, Amount Outstanding | $ (3,395) |

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- Definition Carrying value as of the balance sheet date of short-term borrowings using unsecured obligations issued by banks, corporations and other borrowers to investors. The maturities of these money market securities generally do not exceed 270 days. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03(13)(2)) -URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03(a)(16)) -URI http://asc.fasb.org/extlink&oid=119400593&loc=d3e572229-122910 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(19)(a)(3)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
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- Definition Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 470 -SubTopic 20 -Section 50 -Paragraph 6 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=109500613&loc=SL6036836-161870 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 835 -SubTopic 30 -Section 45 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=114775744&loc=d3e28551-108399 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.22(a)(1)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
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- Definition 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. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(22)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03(16)) -URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03(16)) -URI http://asc.fasb.org/extlink&oid=119400593&loc=d3e572229-122910 + Details
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