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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.

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Amount of income (loss) from continuing operations, including income (loss) from equity method investments, before deduction of income tax expense (benefit), and income (loss) attributable to noncontrolling interest.

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Amount, before accumulated depreciation, of lessor's underlying asset for which right to use has been conveyed to lessee under operating lease.

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Acquisitions (Narrative) (Details) rental_unit in Thousands, $ in Millions		3 Months Ended		9 Months Ended		12 Months Ended
	May 25, 2021 USD ($)	Sep. 30, 2021 USD ($)	Sep. 30, 2020 USD ($)	Sep. 30, 2021 USD ($)	Sep. 30, 2020 USD ($)	Dec. 31, 2020 USD ($)	May 26, 2021 USD ($)	Mar. 31, 2021 USD ($) rental_unit
Business Acquisition [Line Items]
Revenues		$ 2,596	$ 2,187	$ 6,940	$ 6,251
Pretax income		550	275	1,202	752
General Finance Corporation
Business Acquisition [Line Items]
Aggregate consideration paid	$ 1,032
Intangibles							$ 94
Other acquisitions
Business Acquisition [Line Items]
Intangibles		65		65
General Finance Corporation
Business Acquisition [Line Items]
Rental fleet, number of units (approximately) \| rental_unit								100
Property subject to or available for operating lease, gross								$ 650
Revenues		0	81	144	254	$ 342
Pretax income		$ 0	$ 5	$ 9	$ (3)