Loans And Allowance For Loan Losses (Acquired Loans Portfolio) (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019
Business Acquisition [Line Items]
Financing Receivable, Transfer to Held-for-Sale, Allowance for Credit Loss, Expense Reversal	$ 1,430,000
FCB Financial Holdings, Inc.
Business Acquisition [Line Items]
Accretable yield		$ (5,557,334)

Amount of expense reversal of allowance for credit loss on financing receivable transferred to held-for-sale classification.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 948
-SubTopic 310
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=120238483&loc=SL120268815-111004

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=121593590&loc=d3e4428-111522

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration