Shareholders' Equity - Schedule of Forward Sales Executed (Details) - $ / shares	3 Months Ended
Dec. 31, 2019	Sep. 30, 2019
Forward Contract Indexed to Issuer's Equity [Line Items]
Forward sales equity agreement, shares	339,574
Forward sales equity agreement, forward rate per share	$ 107.40
Forward sales equity agreement, settlement in shares	2,249,374	4,629,860
Stock issued during period, new issues (in shares)	2,720,060
Stock issued during period new issues per share	$ 95.22
Forward Sales Equity, Maturity September 2020
Forward Contract Indexed to Issuer's Equity [Line Items]
Forward sales equity agreement, shares	339,574
Forward sales equity agreement, forward rate per share	$ 107.40
Forward sales equity agreement, settlement in shares	2,249,374	2,474,162
Stock issued during period, new issues (in shares)	564,362
Stock issued during period new issues per share	$ 100.21
Forward Sales Equity, Maturity March 2020
Forward Contract Indexed to Issuer's Equity [Line Items]
Forward sales equity agreement, shares	0
Forward sales equity agreement, forward rate per share	$ 0
Forward sales equity agreement, settlement in shares	0	2,155,698
Stock issued during period, new issues (in shares)	2,155,698
Stock issued during period new issues per share	$ 93.88

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The maximum number of shares that could be issued to net share settle a contract, if applicable. If a contract does not have a fixed or determinable maximum number of shares that may be required to be issued, disclose the fact that a potentially infinite number of shares could be issued to settle the contract.

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