Debt - Credit Facility - Additional Information (Details) - USD ($) $ in Millions	1 Months Ended	6 Months Ended
Feb. 28, 2018	Jun. 30, 2021
Debt Instrument [Line Items]
Maximum borrowing capacity		$ 900.0
Revolving Credit Facility
Debt Instrument [Line Items]
Maximum borrowing capacity		$ 300.0
Maturity date		Jun. 29, 2025
Capitalized costs		$ 2.7
Term Loan
Debt Instrument [Line Items]
Capitalized costs		3.1
Term Loan \| Third party
Debt Instrument [Line Items]
Capitalized costs		$ 0.1
$400 Million Term Loan
Debt Instrument [Line Items]
Maturity date		Jun. 29, 2026
Unsecured Debt
Debt Instrument [Line Items]
Maximum borrowing capacity		$ 700.0
Maturity date		Mar. 31, 2023
Unsecured Debt \| Revolving Credit Facility
Debt Instrument [Line Items]
Maximum borrowing capacity	$ 250.0	$ 50.0
Basis spread on variable rate	1.40%	1.40%
Maturity date	Mar. 31, 2022
Unsecured Debt \| Term Loan
Debt Instrument [Line Items]
Maximum borrowing capacity		$ 50.0
Unsecured Debt \| $300 Million Term Loan
Debt Instrument [Line Items]
Maximum borrowing capacity	$ 350.0
Basis spread on variable rate	1.30%
Unsecured Debt \| $300 Million Term Loan \| Revolving Credit Facility
Debt Instrument [Line Items]
Maximum borrowing capacity		300.0
Unsecured Debt \| $400 Million Term Loan
Debt Instrument [Line Items]
Maximum borrowing capacity		$ 400.0
Basis spread on variable rate		1.55%
Unsecured Debt \| $400 Million Term Loan \| Term Loan
Debt Instrument [Line Items]
Maximum borrowing capacity		$ 400.0

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

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.

+ Details

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- Definition

Date the credit facility terminates, in CCYY-MM-DD format.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.19(b),22(b))
-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

+ Details

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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

+ Details

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Balance Type:	credit
Period Type:	instant

- 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.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.17)
-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

+ Details

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- Details

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