Borrowings - Summary of Outstanding Debt (Details) $ in Thousands	6 Months Ended
Jun. 30, 2021 USD ($)
Debt Instrument [Line Items]
Total Outstanding Debt	$ 4,553,237
Debt Instrument, Interest Rate, Effective Percentage	3.50%
Fixed Rate Property Mortgages [Member]
Debt Instrument [Line Items]
Contract Maturity	Sep. 09, 2048
Unsecured Debt [Member]
Debt Instrument [Line Items]
Total Outstanding Debt	$ 4,187,292
Debt Instrument, Interest Rate, Effective Percentage	3.40%
Unsecured Debt [Member] \| Fixed Rate Debt Senior Notes [Member]
Debt Instrument [Line Items]
Debt Instrument, Face Amount	$ 3,922,000
Debt Instrument, Interest Rate, Effective Percentage	3.60%
Contract Maturity	Jan. 27, 2027
Unsecured Debt [Member] \| Commercial Paper Notes [Member] \| Variable Rate Commercial Paper Program [Member]
Debt Instrument [Line Items]
Unsecured Debt	$ 280,000
Debt Instrument, Interest Rate, Effective Percentage	0.20%
Contract Maturity	Jul. 04, 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	$ (14,708)
Secured Debt [Member]
Debt Instrument [Line Items]
Total Outstanding Debt	365,945
Debt issuance costs	$ (3,282)
Debt Instrument, Interest Rate, Effective Percentage	4.40%
Secured Debt [Member] \| Fixed Rate Property Mortgages [Member]
Debt Instrument [Line Items]
SEC Schedule, 12-29, Real Estate Companies, Investment in Mortgage Loans on Real Estate	$ 369,227
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	$ 369,200
Debt Instrument, Interest Rate, Effective Percentage	4.40%
Contract Maturity	Dec. 31, 2048

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.

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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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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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