Aggregate dividends declared during the period for each share of common stock outstanding.

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Face (par) amount of debt instrument at time of issuance.

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The cash outflow associated with the acquisition of long-lived, physical assets that are used in the normal conduct of business to produce goods and services and not intended for resale; includes cash outflows to pay for construction of self-constructed assets.

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The cash inflow from amounts received from issuance of long-term debt that is wholly or partially secured by collateral. Excludes proceeds from tax exempt secured debt.

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Subsequent Events (Details) - USD ($)				3 Months Ended		4 Months Ended	9 Months Ended
Subsequent Events (Details) - USD ($)	Aug. 02, 2019	Jul. 25, 2019	Jul. 08, 2019	Jul. 07, 2019	Jul. 08, 2018	Jan. 20, 2019	Jul. 07, 2019	Jul. 08, 2018
Subsequent Event [Line Items]
Cash dividends declared per common share				$ 0.40	$ 0.40	$ 0.40	$ 1.20	$ 1.20
Payments to acquire commercial property							$ 25,041,000	$ 25,730,000
Subsequent Event
Subsequent Event [Line Items]
Cash dividends declared per common share	$ 0.40
Stock repurchase program, authorized amount	$ 200,000,000
Payments to acquire commercial property		$ 17,300,000
Series 2019-1 3.982% Fixed Rate Senior Secured Notes, Class A-2-I \| Senior Notes \| Subsequent Event
Subsequent Event [Line Items]
Sale of fixed rate senior secured notes			$ 575,000,000.0
Stated interest rate (percent)			3.982%
Series 2019-1 3.982% Fixed Rate Senior Secured Notes, Class A-2-II \| Senior Notes \| Subsequent Event
Subsequent Event [Line Items]
Sale of fixed rate senior secured notes			$ 275,000,000.0
Stated interest rate (percent)			4.476%
Series 2019-1 3.982% Fixed Rate Senior Secured Notes, Class A-2-III \| Senior Notes \| Subsequent Event
Subsequent Event [Line Items]
Sale of fixed rate senior secured notes			$ 450,000,000.0
Stated interest rate (percent)			4.97%
Series 2019-1 Variable Funding Senior Secured Notes, Class A-1 \| Senior Notes \| Subsequent Event
Subsequent Event [Line Items]
Debt issuable under purchase agreement			$ 150,000,000