Shareholders' Equity - Forward Sales Agreement (Details) $ / shares in Units, $ in Thousands	3 Months Ended
Dec. 31, 2021 USD ($) $ / shares shares
Forward Contract Indexed to Issuer's Equity [Line Items]
Shares available (in shares) \| shares	3,094,440
Net proceeds available \| $	$ 294,685
Forward sales equity agreement, forward rate per share \| $ / shares	$ 95.23
Forward Sales Equity Agreement Maturing Quarter Ended September 30, 2022
Forward Contract Indexed to Issuer's Equity [Line Items]
Shares available (in shares) \| shares	1,142,291
Net proceeds available \| $	$ 108,348
Forward sales equity agreement, forward rate per share \| $ / shares	$ 94.85
Forward Sales Equity Agreement Maturing Quarter Ended November 30, 2022
Forward Contract Indexed to Issuer's Equity [Line Items]
Shares available (in shares) \| shares	1,319,733
Net proceeds available \| $	$ 124,680
Forward sales equity agreement, forward rate per share \| $ / shares	$ 94.47
Forward Sales Equity Agreement Maturing Quarter Ended June 30, 2023
Forward Contract Indexed to Issuer's Equity [Line Items]
Shares available (in shares) \| shares	632,416
Net proceeds available \| $	$ 61,657
Forward sales equity agreement, forward rate per share \| $ / shares	$ 97.49

The per share price of the Company's stock at which the contract holder of the freestanding contract has the right to purchase or sell the Company's stock at a future date.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 40
-Section 50
-Paragraph 5
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=123477628&loc=d3e90205-114008

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 480
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (f)(1)
-URI http://asc.fasb.org/extlink&oid=109262807&loc=d3e22047-110879

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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

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- Definition

Amount that would be paid upon settlement of forward contract indexed to equity.

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- Definition

Number of shares as a settlement alternative for each freestanding forward contract.

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