| Credit Facility, Notes Payable and Derivative Instruments - Derivative Instruments (Details) $ in Millions | Sep. 30, 2021  USD ($)  contract | 
|---|---|
| Interest Rate Swap [Member] | |
| Debt Instrument [Line Items] | |
| Derivative, Number of Instruments Held | 6 | 
| Derivative, Notional Amount | $ | $ 350 | 
| Forward Starting Interest Rate Swaps [Member] | |
| Debt Instrument [Line Items] | |
| Derivative, Number of Instruments Held | 5 | 
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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. No definition available. 
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- Definition Nominal or face amount used to calculate payment on derivative. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef 
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- Definition The number of derivative instruments of a particular group held by the entity. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef 
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