DESCRIPTION OF BUSINESS - COVID-19 Update (Details) - USD ($)	6 Months Ended
Jun. 30, 2021	Jun. 30, 2020	Dec. 31, 2020
Unusual or Infrequent Item, or Both [Line Items]
Impairment of real estate	$ 97,100,000	$ 121,500,000
Commercial paper	170,000,000		$ 0
Revolving Credit Facility \| Unsecured revolving credit facility (1)
Unusual or Infrequent Item, or Both [Line Items]
Maximum borrowing capacity	$ 2,750,000,000		$ 3,000,000,000.0

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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- Definition

The charge against earnings in the period to reduce the carrying amount of real property to fair value.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
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- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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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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