Basis of Presentation and Summary of Significant Accounting Policies (Details) $ in Thousands			3 Months Ended	8 Months Ended
		Jan. 01, 2020 USD ($)	Mar. 31, 2020 USD ($) segment market	Aug. 31, 2019 affiliate segment
Basis Of Presentation And Significant Accounting Policies [Line Items]
Number of reportable segments | segment			2	3
Number of affiliates | affiliate				2
Impact due to change in accounting principles	[1]		$ 13,492
Private Banking
Basis Of Presentation And Significant Accounting Policies [Line Items]
Number of geographic markets | market			3
ASU 2016-13
Basis Of Presentation And Significant Accounting Policies [Line Items]
Release in allowance for credit losses on adoption of ASU 2016-13		$ (20,385)
Increase to reserve for unfunded loan commitments		1,400
Impact due to change in accounting principles		$ 13,500

[1] Impact due to the adoption of ASU 2016-13, Financial Instruments (Topic 326) (“ASU 2016-13”). See Part I. Item 1. “Notes to Unaudited Consolidated Financial Statements - Note 15: Recent Accounting Pronouncements.”