Loans Receivable (Interest Income Recognized in loans individually evaluated for impairment) (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Loan [Member]
Impaired Financing Receivable Interest Income Accrual Method [Abstract]
Total Interest Income	$ 965	$ 1,299	$ 1,896	$ 2,578
Impaired Financing Receivable Average Recorded Investment [Abstract]
Total Average Recorded Investment	154,325	147,814	154,460	147,489
Originated Loans [Member]
Impaired Financing Receivable Interest Income Accrual Method [Abstract]
Total Interest Income	965	1,299	1,896	2,578
Impaired Financing Receivable Average Recorded Investment [Abstract]
Total Average Recorded Investment	153,578	147,051	153,713	146,649
Acquired loans accounted for under ASC 310-20 [Member]
Impaired Financing Receivable Interest Income Accrual Method [Abstract]
Total Interest Income	0	0	0	0
Impaired Financing Receivable Average Recorded Investment [Abstract]
Total Average Recorded Investment	0	763	0	840
Commercial Loan [Member] \| Originated Loans [Member]
Impaired Financing Receivable Interest Income Accrual Method [Abstract]
Impaired Financing Receivable With Related Allowance Interest Income Accrual Method	129	193	250	385
Impaired Financing Receivable With No Related Allowance Interest Income Accrual Method	131	383	262	766
Impaired Financing Receivable Average Recorded Investment [Abstract]
Impaired Financing Receivable With Related Allowance Average Recorded Investment	46,976	14,908	49,154	13,859
Impaired Financing Receivable With No Related Allowance Average Recorded Investment	22,129	44,528	19,946	44,211
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	0
Impaired Financing Receivable With No Related Allowance Interest Income Accrual Method	0	0	0	0
Impaired Financing Receivable Average Recorded Investment [Abstract]
Impaired Financing Receivable With Related Allowance Average Recorded Investment	747	0	747	0
Impaired Financing Receivable With No Related Allowance Average Recorded Investment	0	763	0	840
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	705	723	1,384	1,427
Impaired Financing Receivable Average Recorded Investment [Abstract]
Impaired Financing Receivable With Related Allowance Average Recorded Investment	$ 84,473	$ 87,615	$ 84,613	$ 88,579

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://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 15
-Subparagraph (c)(1)
-URI http://asc.fasb.org/extlink&oid=84173941&loc=d3e5212-111524

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 17
-URI http://asc.fasb.org/extlink&oid=84173941&loc=d3e5258-111524

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Amount of interest income recognized that the financing receivables (with related allowance for credit losses and without a related allowance for credit losses) were impaired.

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Amount of average investment of impaired financing receivables for which there is no related allowance for credit losses.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 17
-URI http://asc.fasb.org/extlink&oid=84173941&loc=d3e5258-111524

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 15
-Subparagraph (c)(1)
-URI http://asc.fasb.org/extlink&oid=84173941&loc=d3e5212-111524

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Amount of interest income, recognized on accrual basis, on financing receivables that are recognized as impaired, for which there is no related allowance for credit losses.

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