Loans (Interest Income Recognized in loans individually evaluated for impairment) (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Originated Loans [Member]
Impaired Financing Receivable Interest Income Accrual Method [Abstract]
Total Interest Income	$ 4,250	$ 5,271	$ 5,714
Impaired Financing Receivable Average Recorded Investment [Abstract]
Total Average Recorded Investment	147,310	155,420	149,877
Acquired loans accounted for under ASC 310-20 [Member]
Impaired Financing Receivable Interest Income Accrual Method [Abstract]
Total Interest Income	4,250	5,271	5,714
Impaired Financing Receivable Average Recorded Investment [Abstract]
Total Average Recorded Investment	148,011	156,167	150,671
Commercial Loan [Member] \| Originated Loans [Member]
Impaired Financing Receivable Interest Income Accrual Method [Abstract]
Impaired Financing Receivable With Related Allowance Interest Income Accrual Method	503	1,624	1,538
Impaired Financing Receivable With No Related Allowance Interest Income Accrual Method	1,086	1,091	875
Impaired Financing Receivable Average Recorded Investment [Abstract]
Impaired Financing Receivable With Related Allowance Average Recorded Investment	41,868	44,727	25,797
Impaired Financing Receivable With No Related Allowance Average Recorded Investment	32,269	26,199	36,666
Commercial Loan [Member] \| Acquired loans accounted for under ASC 310-20 [Member]
Impaired Financing Receivable Interest Income Accrual Method [Abstract]
Impaired Financing Receivable With Related Allowance Interest Income Accrual Method	0	0	0
Impaired Financing Receivable Average Recorded Investment [Abstract]
Impaired Financing Receivable With Related Allowance Average Recorded Investment	701	747	794
Troubled Debt Restructuring [Member] \| Originated Loans [Member]
Impaired Financing Receivable Interest Income Accrual Method [Abstract]
Impaired Financing Receivable With Related Allowance Interest Income Accrual Method	2,661	2,556	3,301
Impaired Financing Receivable Average Recorded Investment [Abstract]
Impaired Financing Receivable With Related Allowance Average Recorded Investment	$ 73,173	$ 84,494	$ 87,414

Average amount of investment of impaired financing receivables with related allowance for credit losses and without a related allowance for credit losses.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 15
-Subparagraph (c)(1)
-URI http://asc.fasb.org/extlink&oid=118936363&loc=d3e5212-111524

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 17
-URI http://asc.fasb.org/extlink&oid=118936363&loc=d3e5258-111524

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 17
-URI http://asc.fasb.org/extlink&oid=118936363&loc=d3e5258-111524

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-Publisher FASB
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-Section 50
-Paragraph 15
-Subparagraph (c)(1)
-URI http://asc.fasb.org/extlink&oid=118936363&loc=d3e5212-111524

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