Variable Interest Entities (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Variable Interest Entity [Line Items]
Assets in partnership	$ 26,604,254	$ 24,610,225
Variable Interest Entity Not Primary Beneficiary [Member]
Variable Interest Entity [Line Items]
Assets in partnership	$ 295,600

Sum of the carrying amounts as of the balance sheet date of all assets that are recognized. Assets are probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

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+ Details