Supplemental Detail for Certain Components of Consolidated Balance Sheets - Accounts Receivable (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Accounts Receivable
Straight-line rent receivables, net	$ 211,522	$ 174,074
Client receivables, net	130,207	111,627
Accounts receivable	$ 341,729	$ 285,701

Amount of excess of rental income recognized over rental payment required by lease.

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant