Acquisitions (Narrative) (Details) - USD ($) $ in Thousands			3 Months Ended
	Jan. 01, 2019	Oct. 01, 2016	Mar. 31, 2020	Mar. 31, 2019
Business Acquisition [Line Items]
Merger-related expense			$ 0	$ 49,738
FCB Financial Holdings, Inc.
Business Acquisition [Line Items]
Consideration transferred	$ 1,630,000
Loans	9,290,000		90,300
Deposits	$ 10,930,000
Merger-related expense				$ 49,738
Global One
Business Acquisition [Line Items]
Earnout liability			$ 11,000
Global One | Minimum
Business Acquisition [Line Items]
Period of additional annual payments		3 years
Global One | Maximum
Business Acquisition [Line Items]
Period of additional annual payments		5 years