Loans Receivable and Allowance for Credit Losses (Loans Modified as TDRs that Subsequently Defaulted) (Details) $ in Thousands	12 Months Ended
Dec. 31, 2019 USD ($) loan	Dec. 31, 2018 USD ($) loan	Dec. 31, 2017 USD ($) loan
Financing Receivable, Troubled Debt Restructuring [Line Items]
Additional funds committed to lend to borrowers whose terms have been modified	$ 2,200	$ 3,900
Non-PCI loans \| Commercial Lending \| C&I
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Loans \| loan	3	4	3
Recorded Investment	$ 13,112	$ 1,890	$ 8,659
Non-PCI loans \| Commercial Lending \| CRE
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Loans \| loan	0	1	0
Recorded Investment	$ 0	$ 186	$ 0
Non-PCI loans \| Commercial Lending \| Total CRE
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Loans \| loan	0	1	0
Recorded Investment	$ 0	$ 186	$ 0
Non-PCI loans \| Consumer Lending \| HELOCs
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Loans \| loan	0	1	0
Recorded Investment	$ 0	$ 150	$ 0
Non-PCI loans \| Consumer Lending \| Total residential mortgage
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Loans \| loan	0	1	0
Recorded Investment	$ 0	$ 150	$ 0

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Number of financing receivable contracts modified as troubled debt restructuring within previous 12 months, with subsequent payment default.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 34
-URI http://asc.fasb.org/extlink&oid=118936363&loc=SL6953682-111524

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Amount of financing receivable modified as troubled debt restructuring within previous 12 months, with subsequent payment default.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 34
-Subparagraph (a)(2)
-URI http://asc.fasb.org/extlink&oid=118936363&loc=SL6953682-111524

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Amount of unfunded portion of contractual agreement to lend funds to borrower for financing receivable modified as troubled debt restructuring.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 40
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=118939409&loc=d3e18794-111554

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