Fair Value Measurements - Fair Value by Balance Sheet Grouping (Details) - Fair Value Measurements Using Level 3 - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Carrying Amount
Liabilities
Carrying value of debt	$ 1,529,113	$ 1,341,242
Fair Value
Liabilities
Fair value of debt	$ 1,533,534	$ 1,368,151

Fair value portion of debt instrument payable, including, but not limited to, notes payable and loans payable.

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Publisher FASB
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Name:	us-gaap_DebtInstrumentFairValue
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant