Summary of Significant Accounting Policies Residual Values (Details) - USD ($)	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Jan. 01, 2018
Property Subject to or Available for Operating Lease [Line Items]
Property Subject to or Available for Operating Lease, Net		$ 8,364,484,000	$ 7,370,519,000
Special Container Units [Member]
Property Subject to or Available for Operating Lease [Line Items]
Property Subject to or Available for Operating Lease, Net		$ 287,869,000	$ 265,666,000
Dry Container Units 20 Foot [Member]
Property Subject to or Available for Operating Lease [Line Items]
Property Subject to or Available for Operating Lease Net Useful Life Average		13 years	13 years
Property Subject to or Available for Operating Lease Net Salvage Value		$ 1,000	$ 1,000
Dry Container Units 40 Foot [Member]
Property Subject to or Available for Operating Lease [Line Items]
Property Subject to or Available for Operating Lease Net Useful Life Average		13 years	13 years
Property Subject to or Available for Operating Lease Net Salvage Value		$ 1,200	$ 1,200
Dry Container Units 40 Foot High Cube [Member]
Property Subject to or Available for Operating Lease [Line Items]
Property Subject to or Available for Operating Lease Net Useful Life Average		13 years	13 years
Property Subject to or Available for Operating Lease Net Salvage Value		$ 1,400	$ 1,400
Refrigerated Container Units 20 Foot [Member]
Property Subject to or Available for Operating Lease [Line Items]
Property Subject to or Available for Operating Lease Net Useful Life Average		12 years	12 years
Property Subject to or Available for Operating Lease Net Salvage Value				$ 2,350
Refrigerated Container Units 40 Foot High Cube [Member]
Property Subject to or Available for Operating Lease [Line Items]
Property Subject to or Available for Operating Lease Net Useful Life Average		12 years	12 years
Property Subject to or Available for Operating Lease Net Salvage Value				3,350
Special Container Units 40 Foot Flat Rack [Member]
Property Subject to or Available for Operating Lease [Line Items]
Property Subject to or Available for Operating Lease Net Salvage Value				1,700
Special Container Units 40 Foot Open Top [Member]
Property Subject to or Available for Operating Lease [Line Items]
Property Subject to or Available for Operating Lease Net Salvage Value				$ 2,300
Tank Container Units [Member]
Property Subject to or Available for Operating Lease [Line Items]
Property Subject to or Available for Operating Lease, Net		$ 105,821,000	$ 107,933,000
Property Subject to or Available for Operating Lease Net Useful Life Average		20 years	20 years
Property Subject to or Available for Operating Lease Net Salvage Value		$ 3,000	$ 3,000
Chassis [Member]
Property Subject to or Available for Operating Lease [Line Items]
Property Subject to or Available for Operating Lease, Net		$ 132,312,000	$ 119,320,000
Property Subject to or Available for Operating Lease Net Useful Life Average		20 years	20 years
Property Subject to or Available for Operating Lease Net Salvage Value		$ 1,200	$ 1,200
Dry Container Units [Member]
Property Subject to or Available for Operating Lease [Line Items]
Property Subject to or Available for Operating Lease, Net		5,941,097,000	4,839,648,000
Refrigerated Container Units [Member]
Property Subject to or Available for Operating Lease [Line Items]
Property Subject to or Available for Operating Lease, Net		1,897,385,000	2,037,952,000
Maximum [Member] | Refrigerated Container Units 20 Foot [Member]
Property Subject to or Available for Operating Lease [Line Items]
Property Subject to or Available for Operating Lease Net Salvage Value		2,500	2,500
Maximum [Member] | Refrigerated Container Units 40 Foot High Cube [Member]
Property Subject to or Available for Operating Lease [Line Items]
Property Subject to or Available for Operating Lease Net Salvage Value		$ 3,500	$ 3,500
Maximum [Member] | Special Container Units 40 Foot Flat Rack [Member]
Property Subject to or Available for Operating Lease [Line Items]
Property Subject to or Available for Operating Lease Net Useful Life Average		14 years	14 years
Property Subject to or Available for Operating Lease Net Salvage Value		$ 3,000	$ 3,000
Maximum [Member] | Special Container Units 40 Foot Open Top [Member]
Property Subject to or Available for Operating Lease [Line Items]
Property Subject to or Available for Operating Lease Net Useful Life Average		14 years	14 years
Property Subject to or Available for Operating Lease Net Salvage Value		$ 2,500	$ 2,500
Minimum [Member] | Refrigerated Container Units 20 Foot [Member]
Property Subject to or Available for Operating Lease [Line Items]
Property Subject to or Available for Operating Lease Net Salvage Value		2,250	2,250
Minimum [Member] | Refrigerated Container Units 40 Foot High Cube [Member]
Property Subject to or Available for Operating Lease [Line Items]
Property Subject to or Available for Operating Lease Net Salvage Value		$ 3,250	$ 3,250
Minimum [Member] | Special Container Units 40 Foot Flat Rack [Member]
Property Subject to or Available for Operating Lease [Line Items]
Property Subject to or Available for Operating Lease Net Useful Life Average		12 years	12 years
Property Subject to or Available for Operating Lease Net Salvage Value		$ 1,500	$ 1,500
Minimum [Member] | Special Container Units 40 Foot Open Top [Member]
Property Subject to or Available for Operating Lease [Line Items]
Property Subject to or Available for Operating Lease Net Useful Life Average		12 years	12 years
Property Subject to or Available for Operating Lease Net Salvage Value		$ 2,300	$ 2,300
Scenario, Forecast [Member] | Special Container Units 40 Foot Open Top [Member]
Property Subject to or Available for Operating Lease [Line Items]
Property Subject to or Available for Operating Lease Net Useful Life Average	16 years