Consolidation of Variable Interest Entities (Details)	12 Months Ended
	Dec. 31, 2020 USD ($) item	Dec. 31, 2019 USD ($) item	Dec. 31, 2018 USD ($) item	Dec. 31, 2017 USD ($)
Variable Interest Entity [Line Items]
Net book value	$ 1,781,321,000	$ 1,820,735,000
Collateralized Financing Obligations [Member]
Variable Interest Entity [Line Items]
Long-term debt	69,600,000
Term Loan [Member]
Variable Interest Entity [Line Items]
Long-term debt	31,200,000
Variable Interest Entity, Primary Beneficiary [Member]
Variable Interest Entity [Line Items]
Net book value	77,907,000	101,907,000
Cash	$ 26,856,000	$ 26,594,000	$ 25,211,000	$ 20,685,000
Variable Interest Entity, Primary Beneficiary [Member] | Containers [Member]
Variable Interest Entity [Line Items]
Number of types of container fund arrangements | item	2
Number of container portfolios sold | item	0	0	0
Net book value	$ 80,600,000
Cash	26,900,000
Gain (loss) recognized on initial consolidation of VIEs	0
Carrying value of assets sold	$ 65,000,000.0	$ 40,600,000