Borrowings - Summary of Outstanding Debt (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2020	Dec. 31, 2019
Debt Instrument [Line Items]
Unsecured Debt	$ 3,859,040	$ 3,828,201
Total Outstanding Debt	$ 4,483,693
Debt Instrument, Interest Rate, Effective Percentage	3.80%
Unsecured Debt [Member]
Debt Instrument [Line Items]
Total Outstanding Debt	$ 3,859,040
Debt Instrument, Interest Rate, Effective Percentage	3.70%
Unsecured Debt [Member] \| Variable Rate Credit Facility [Member]
Debt Instrument [Line Items]
Line of Credit Facility, Amount Outstanding	$ 100,000
Debt Instrument, Interest Rate, Effective Percentage	1.70%
Contract Maturity	May 20, 2023
Unsecured Debt [Member] \| Fixed Rate Debt Senior Notes [Member]
Debt Instrument [Line Items]
Debt Instrument, Face Amount	$ 3,472,000
Debt Instrument, Interest Rate, Effective Percentage	3.90%
Contract Maturity	Jul. 19, 2026
Unsecured Debt [Member] \| Variable Rate Debt [Member]
Debt Instrument [Line Items]
Unsecured Debt	$ 300,000
Debt Instrument, Interest Rate, Effective Percentage	2.50%
Contract Maturity	Mar. 01, 2022
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	$ (12,960)
Secured Debt [Member]
Debt Instrument [Line Items]
Total Outstanding Debt	$ 624,653
Debt Instrument, Interest Rate, Effective Percentage	4.50%
Secured Debt [Member] \| Fair Market Value Adjustment and Debt Issuance Cost [Member]
Debt Instrument [Line Items]
Line of Credit Facility, Amount Outstanding	$ (3,424)
Secured Debt [Member] \| Fixed Rate Debt Senior Notes [Member]
Debt Instrument [Line Items]
Debt Instrument, Face Amount	$ 628,077
Debt Instrument, Interest Rate, Effective Percentage	4.50%
Contract Maturity	Apr. 17, 2037

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

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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.

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No definition available.

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- Definition

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

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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.

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- Definition

Amount of investment in mortgage loan on real estate by entity with substantial portion of business acquiring and holding investment real estate or interest in real estate.

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- Definition

Including the current and noncurrent portions, aggregate carrying amount of all types of notes payable, as of the balance sheet date, with initial maturities beyond one year or beyond the normal operating cycle, if longer.

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Including the current and noncurrent portions, carrying value as of the balance sheet date of uncollateralized debt obligations (with maturities initially due after one year or beyond the operating cycle if longer).

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