Financial Data of Busines Segments (Details)			3 Months Ended		12 Months Ended
	Dec. 29, 2020 USD ($)	Dec. 29, 2020 EUR (€)	Mar. 31, 2022 USD ($)	Mar. 31, 2021 USD ($) AircraftEngines	Dec. 31, 2022 USD ($) AircraftEngines	Dec. 31, 2021 USD ($)	Dec. 31, 2020 USD ($)
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Lease Income					$ 1,154,600,000	$ 1,140,500,000	$ 1,087,500,000
MarineOperatingRevenue					18,900,000	19,100,000	15,600,000
Other revenue					99,500,000	97,800,000	106,100,000
Total Revenues					1,273,000,000	1,257,400,000	1,209,200,000
Maintenance Expense					292,700,000	297,100,000	315,500,000
Marine operating expense					14,100,000	17,500,000	19,700,000
Depreciation					357,500,000	364,400,000	330,500,000
Operating Lease, Expense					36,100,000	39,200,000	49,300,000
Other operating expense					37,400,000	44,000,000.0	35,300,000
Total Expenses					737,800,000	762,200,000	750,300,000
Net gain on asset dispositions					77,900,000	105,900,000	41,700,000
Interest Income (Expense), Net					(214,000,000.0)	(204,000,000.0)	(190,300,000)
Other (expense) income					(27,000,000.0)	(3,700,000)	(13,000,000.0)
Share of affiliates' earnings (pre-tax)					45,900,000	56,500,000	95,800,000
Segment Profit Loss					418,000,000.0	449,900,000	393,100,000
Selling, general and administrative					195,000,000.0	198,300,000	172,000,000.0
Income tax benefit					54,800,000	53,200,000	37,300,000
Income from continuing operations					155,900,000	143,100,000	150,200,000
Net Income					155,900,000	143,100,000	151,300,000
Disposition Gains on Owned Assets					104,100,000	82,400,000	39,400,000
Nonoperating Income, Residual Sharing Income					5,600,000	8,900,000	2,500,000
Asset Impairment Charges					(48,900,000)	(2,400,000)	(300,000)
Identifiable assets					10,072,000,000	9,541,700,000	8,937,600,000
Nonremarketing Disposition Gain (Loss)					17,100,000	17,000,000.0	100,000
Portfolio Investments and Capital Additions					1,255,800,000	1,131,900,000	1,064,000,000
Investments in Affiliated Companies					575,100,000	588,400,000	584,700,000
Assets of Continuing Operations					10,072,000,000	9,541,700,000	8,937,600,000
Payments to Acquire Property, Plant, and Equipment					(1,255,800,000)	(1,130,100,000)	(860,800,000)
Total Discontinued Operations, Net of Taxes					0	0	1,100,000
Provision for Income Taxes, Equity Method Investment					12,300,000	55,300,000	33,600,000
Trifleet Leasing Holding B.V.
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Payments to acquire business, gross	$ 203,200,000	€ 165,000,000
Parent [Member]
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Income tax benefit					67,100,000	108,500,000	70,900,000
Other Business Segments [Member]
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Lease Income					29,400,000	25,000,000.0	0
MarineOperatingRevenue					0	0	0
Other revenue					6,700,000	8,700,000	0
Total Revenues					36,100,000	33,700,000	0
Maintenance Expense					2,800,000	4,100,000	0
Marine operating expense					0	0	0
Depreciation					12,000,000.0	12,100,000	0
Operating Lease, Expense					0	0	0
Other operating expense					2,300,000	3,000,000.0	0
Total Expenses					17,100,000	19,200,000	0
Net gain on asset dispositions					500,000	900,000	0
Interest Income (Expense), Net					(4,800,000)	(6,000,000.0)	7,700,000
Other (expense) income					(18,600,000)	(10,700,000)	(3,100,000)
Share of affiliates' earnings (pre-tax)					0	0	0
Segment Profit Loss					(3,900,000)	(1,300,000)	4,600,000
Disposition Gains on Owned Assets					300,000	500,000	0
Nonoperating Income, Residual Sharing Income					0	0	0
Asset Impairment Charges					0	0	0
Identifiable assets							541,300,000
Nonremarketing Disposition Gain (Loss)					200,000	400,000	0
Portfolio Investments and Capital Additions					46,300,000	31,200,000	205,500,000
Investments in Affiliated Companies					0	0	0
Assets of Continuing Operations					745,300,000	621,400,000
Rail North America [Member]
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Lease Income					826,000,000.0	814,500,000	838,300,000
MarineOperatingRevenue					0	0	0
Other revenue					82,000,000.0	77,200,000	95,800,000
Total Revenues					908,000,000.0	891,700,000	934,100,000
Maintenance Expense					238,500,000	235,400,000	264,700,000
Marine operating expense					0	0	0
Depreciation					258,600,000	261,100,000	258,600,000
Operating Lease, Expense					36,100,000	39,200,000	49,300,000
Other operating expense					24,500,000	30,300,000	27,300,000
Total Expenses					557,700,000	566,000,000.0	599,900,000
Net gain on asset dispositions					119,700,000	94,300,000	38,300,000
Interest Income (Expense), Net					(144,600,000)	(136,200,000)	(139,900,000)
Other (expense) income					(4,600,000)	1,600,000	(4,900,000)
Share of affiliates' earnings (pre-tax)					500,000	0	(100,000)
Segment Profit Loss					321,300,000	285,400,000	227,600,000
Disposition Gains on Owned Assets					102,200,000	80,700,000	38,800,000
Nonoperating Income, Residual Sharing Income					2,400,000	900,000	400,000
Asset Impairment Charges					0	(2,400,000)	(300,000)
Identifiable assets							5,944,400,000
Nonremarketing Disposition Gain (Loss)					15,100,000	15,100,000	(600,000)
Portfolio Investments and Capital Additions					815,900,000	574,400,000	642,000,000.0
Investments in Affiliated Companies							0
Assets of Continuing Operations					6,445,700,000	6,141,700,000
Rail North America [Member] | RailPulse
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Investments in Affiliated Companies					800,000	300,000
Rail International [Member]
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Lease Income					266,200,000	272,900,000	248,400,000
MarineOperatingRevenue					0	0	0
Other revenue					9,100,000	11,400,000	9,700,000
Total Revenues					275,300,000	284,300,000	258,100,000
Maintenance Expense					51,400,000	57,600,000	50,800,000
Marine operating expense					0	0	0
Depreciation					69,100,000	73,600,000	66,600,000
Operating Lease, Expense					0	0	0
Other operating expense					8,300,000	9,000,000.0	7,500,000
Total Expenses					128,800,000	140,200,000	124,900,000
Net gain on asset dispositions					(11,200,000)	2,700,000	1,200,000
Interest Income (Expense), Net					(45,600,000)	(45,200,000)	(45,900,000)
Other (expense) income					(3,800,000)	3,400,000	(5,000,000.0)
Share of affiliates' earnings (pre-tax)					0	0	0
Segment Profit Loss					85,900,000	105,000,000.0	83,500,000
Disposition Gains on Owned Assets					1,600,000	1,200,000	500,000
Nonoperating Income, Residual Sharing Income					0	0	0
Asset Impairment Charges					(14,600,000)	0	0
Identifiable assets							1,745,800,000
Nonremarketing Disposition Gain (Loss)					1,800,000	1,500,000	700,000
Portfolio Investments and Capital Additions					243,900,000	173,300,000	216,000,000.0
Investments in Affiliated Companies					0	0	0
Assets of Continuing Operations					1,774,400,000	1,729,900,000
Portfolio Management [Member]
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Lease Income					33,000,000.0	28,100,000	800,000
MarineOperatingRevenue					18,900,000	19,100,000	15,600,000
Other revenue					1,700,000	500,000	600,000
Total Revenues					53,600,000	47,700,000	17,000,000.0
Maintenance Expense					0	0	0
Marine operating expense					14,100,000	17,500,000	19,700,000
Depreciation					17,800,000	17,600,000	5,300,000
Operating Lease, Expense					0	0	0
Other operating expense					2,300,000	1,700,000	500,000
Total Expenses					34,200,000	36,800,000	25,500,000
Net gain on asset dispositions					(31,100,000)	8,000,000.0	2,200,000
Interest Income (Expense), Net					(19,000,000.0)	(16,600,000)	(12,200,000)
Other (expense) income					0	2,000,000.0	0
Share of affiliates' earnings (pre-tax)					45,400,000	56,500,000	95,900,000
Segment Profit Loss					14,700,000	60,800,000	77,400,000
Disposition Gains on Owned Assets					0	0	100,000
Nonoperating Income, Residual Sharing Income					3,200,000	8,000,000.0	2,100,000
Asset Impairment Charges					(34,300,000)	0	0
Nonremarketing Disposition Gain (Loss)					0	0	0
Portfolio Investments and Capital Additions					149,700,000	353,000,000.0	500,000
Investments in Affiliated Companies						588,100,000	584,700,000
Assets of Continuing Operations					$ 1,106,600,000	1,048,700,000	$ 706,100,000
Number Of Aircraft Engines | AircraftEngines				14	5
Payments to Acquire Property, Plant, and Equipment			$ (150,000,000)	$ 352,000,000	$ (150,000,000)
Portfolio Management [Member] | Rolls Royce Partners Finance [Member]
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Investments in Affiliated Companies					$ 574,300,000	$ 588,100,000