Allowance for Credit Losses (Impairment By Loan Class) (Details) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Loan loss allowances, impaired financing receivable, evaluated individually or collectively
Loans Individually Evaluated for Impairment, Recorded Investment	$ 3,349	$ 12,675
Loans Individually Evaluated for Impairment, Allowance	458	365
Loans Collectively Evaluated for Impairment, Recorded Investment	7,021,031	6,882,271
Loans Collectively Evaluated for Impairment, Allowance	84,815	59,913
Commercial
Loan loss allowances, impaired financing receivable, evaluated individually or collectively
Loans Individually Evaluated for Impairment, Recorded Investment	1,649	1,935
Loans Individually Evaluated for Impairment, Allowance	342	249
Loans Collectively Evaluated for Impairment, Recorded Investment	1,367,362	1,290,725
Loans Collectively Evaluated for Impairment, Allowance	18,725	10,895
Real estate - construction
Loan loss allowances, impaired financing receivable, evaluated individually or collectively
Loans Individually Evaluated for Impairment, Recorded Investment	936	938
Loans Individually Evaluated for Impairment, Allowance	116	116
Loans Collectively Evaluated for Impairment, Recorded Investment	2,215,804	2,184,945
Loans Collectively Evaluated for Impairment, Allowance	37,305	18,037
Commercial Real Estate: Farmland and Commercial
Loan loss allowances, impaired financing receivable, evaluated individually or collectively
Loans Individually Evaluated for Impairment, Recorded Investment	517	1,208
Loans Collectively Evaluated for Impairment, Recorded Investment	1,932,848	1,895,539
Loans Collectively Evaluated for Impairment, Allowance	15,004	16,533
Commercial Real Estate: Multifamily
Loan loss allowances, impaired financing receivable, evaluated individually or collectively
Loans Individually Evaluated for Impairment, Recorded Investment	152	165
Loans Collectively Evaluated for Impairment, Recorded Investment	202,298	190,265
Loans Collectively Evaluated for Impairment, Allowance	1,758	1,786
Residential First Lien
Loan loss allowances, impaired financing receivable, evaluated individually or collectively
Loans Individually Evaluated for Impairment, Recorded Investment	92	6,278
Loans Collectively Evaluated for Impairment, Recorded Investment	431,496	427,623
Loans Collectively Evaluated for Impairment, Allowance	2,782	3,762
Residential Junior Lien
Loan loss allowances, impaired financing receivable, evaluated individually or collectively
Loans Individually Evaluated for Impairment, Recorded Investment		692
Loans Collectively Evaluated for Impairment, Recorded Investment	686,604	705,784
Loans Collectively Evaluated for Impairment, Allowance	8,452	7,535
Consumer
Loan loss allowances, impaired financing receivable, evaluated individually or collectively
Loans Individually Evaluated for Impairment, Recorded Investment	3	1,195
Loans Collectively Evaluated for Impairment, Recorded Investment	45,437	46,605
Loans Collectively Evaluated for Impairment, Allowance	323	542
Foreign
Loan loss allowances, impaired financing receivable, evaluated individually or collectively
Loans Individually Evaluated for Impairment, Recorded Investment		264
Loans Collectively Evaluated for Impairment, Recorded Investment	139,182	140,785
Loans Collectively Evaluated for Impairment, Allowance	$ 466	$ 823

The valuation allowance for financing receivables that are expected to be uncollectible that were collectively evaluated for impairment.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 11B
-Subparagraph (g)
-URI http://asc.fasb.org/extlink&oid=118936363&loc=SL6953423-111524

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Amount of valuation allowance for financing receivables that are expected to be uncollectible that were individually evaluated for impairment.

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The balance of financing receivables that were collectively evaluated for impairment.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 11B
-Subparagraph (h)
-URI http://asc.fasb.org/extlink&oid=118936363&loc=SL6953423-111524

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The balance of financing receivables that were individually evaluated for impairment.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 11B
-Subparagraph (h)
-URI http://asc.fasb.org/extlink&oid=118936363&loc=SL6953423-111524

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