Debt - Narrative (Details)	6 Months Ended
Jun. 30, 2020 USD ($) instrument extension	Dec. 31, 2019 USD ($)
Unsecured debt
Debt Instrument [Line Items]
Unamortized discount (premium), net	$ 5,700,000	$ 12,200,000
Unamortized debt issuance expense	28,500,000	24,500,000
Lines of credit
Debt Instrument [Line Items]
Unamortized debt issuance expense	$ 4,200,000	3,800,000
Number of lines of unsecured credit (in instruments) \| instrument	2
Aggregate borrowing capacity	$ 1,240,000,000
Number of extension options (in extensions) \| extension	1
Extension period	18 months
Lines of credit \| LIBOR
Debt Instrument [Line Items]
Basis spread on variable rate	0.825%
Lines of credit \| Working capital line of credit
Debt Instrument [Line Items]
Aggregate borrowing capacity	$ 35,000,000.0
Lines of credit \| Working capital line of credit \| LIBOR
Debt Instrument [Line Items]
Basis spread on variable rate	0.825%
Mortgage notes payable, net
Debt Instrument [Line Items]
Unamortized discount (premium), net	$ (4,600,000)	(5,900,000)
Unamortized debt issuance expense	$ 2,200,000	$ 2,600,000

Debt Instrument, Terms, Extension Period

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- Definition

Debt Instrument, Terms, Number Of Extension Options

+ References

No definition available.

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- Definition

Line Of Credit Facility, Number Of Lines Of Credit

+ References

No definition available.

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- Definition

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

+ References

No definition available.

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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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- Definition

Amount, after accumulated amortization, of debt discount (premium).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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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.

+ References

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- Definition

The remaining balance of debt issuance expenses that were capitalized and are being amortized against income over the lives of the respective bond issues. This does not include the amounts capitalized as part of the cost of the utility plant or asset.

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