Transfers of Financial Assets (Loans sold) (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Servicing Assets at Fair Value [Line Items]
Net gain on sale	$ 18,295	$ 6,115	$ 4,424
Residential Mortgage [Member]
Servicing Assets at Fair Value [Line Items]
Proceeds from sale	486,341	216,239	188,025
Net gain on sale	15,305	4,031	3,146
Ancillary Fee Income Generated by Servicing Financial Assets, Amount	3,230	1,614	1,544
Fair value option adjustment	(240)	470	(266)
Commercial Loan [Member]
Servicing Assets at Fair Value [Line Items]
Net gain on sale	300	700
Residential Mortgage Loans Servicing Retained [Member] \| Residential Mortgage [Member]
Servicing Assets at Fair Value [Line Items]
Proceeds from sale	$ 464,736	$ 199,114	$ 166,909

All amounts that are due to the servicer of a financial asset, excluding contractually specified servicing fees and late fees.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 50
-Section 50
-Paragraph 2
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=116651436&loc=d3e122596-111746

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Amount of addition (reduction) to the amount at which an asset could be incurred (settled) in a current transaction between willing parties.

+ References

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The net gain (loss) resulting from a sale of loans, including adjustments to record loans classified as held-for-sale at the lower-of-cost-or-market and fair value adjustments to loan held for investment purposes.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 220
-Section S99
-Paragraph 1
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
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-URI http://asc.fasb.org/extlink&oid=121586364&loc=d3e3602-108585

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 220
-Section S99
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The cash inflow from sales of loans that are secured with real estate mortgages and are held with the intention to resell in the near future.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 21
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-URI http://asc.fasb.org/extlink&oid=121586364&loc=d3e3536-108585

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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