Loans and Allowance for Credit Losses (Details 1) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2018	Mar. 31, 2017	Mar. 31, 2018	Mar. 31, 2017
Allowance for Credit Losses, beginning balance	$ 64,758	$ 59,074
Loans charged-off	(1,106)	(700)
Recoveries of loans previously charged-off	186	77
Net loans charged-off	(920)	(623)
Provision for credit losses	1,969	1,397
Allowance for Credit Losses, ending balance	65,807	59,848
Individually evaluated for impairment			$ 6,722	$ 5,268
Collectively evaluated for impairment			59,085	54,580
Balance	65,807	59,848	65,807	59,848
Commercial [Member]
Allowance for Credit Losses, beginning balance	13,102	14,700
Loans charged-off	(853)	(137)
Recoveries of loans previously charged-off	3	13
Net loans charged-off	(850)	(124)
Provision for credit losses	1,106	7
Allowance for Credit Losses, ending balance	13,358	14,583
Individually evaluated for impairment			3,014	3,030
Collectively evaluated for impairment			10,344	11,553
Balance	13,102	14,700	13,358	14,583
Income Producing - Commercial Real Estate [Member]
Allowance for Credit Losses, beginning balance	25,376	21,105
Loans charged-off	(121)	(500)
Recoveries of loans previously charged-off		50
Net loans charged-off	(121)	(450)
Provision for credit losses	1,213	729
Allowance for Credit Losses, ending balance	26,468	21,384
Individually evaluated for impairment			2,628	1,488
Collectively evaluated for impairment			23,840	19,896
Balance	25,376	21,105	26,468	21,384
Owner Occupied - Commercial Real Estate - [Member]
Allowance for Credit Losses, beginning balance	5,934	4,010
Loans charged-off	(132)
Recoveries of loans previously charged-off	1	1
Net loans charged-off	(131)	1
Provision for credit losses	(332)	15
Allowance for Credit Losses, ending balance	5,471	4,026
Individually evaluated for impairment			500	350
Collectively evaluated for impairment			4,971	3,676
Balance	5,934	4,010	5,471	4,026
Real Estate Mortgage - Residential [Member]
Allowance for Credit Losses, beginning balance	944	1,284
Loans charged-off
Recoveries of loans previously charged-off	2	2
Net loans charged-off	2	2
Provision for credit losses	(212)	(180)
Allowance for Credit Losses, ending balance	734	1,106
Individually evaluated for impairment
Collectively evaluated for impairment			734	1,106
Balance	944	1,284	734	1,106
Construction - Commercial And Residencial [Member]
Allowance for Credit Losses, beginning balance	18,492	16,487
Loans charged-off
Recoveries of loans previously charged-off	60	3
Net loans charged-off	60	3
Provision for credit losses	190	866
Allowance for Credit Losses, ending balance	18,742	17,356
Individually evaluated for impairment			500	350
Collectively evaluated for impairment			18,242	17,006
Balance	18,492	16,487	18,742	17,356
Home Equity [Member]
Allowance for Credit Losses, beginning balance	770	1,328
Loans charged-off
Recoveries of loans previously charged-off	117	1
Net loans charged-off	117	1
Provision for credit losses	(188)	(241)
Allowance for Credit Losses, ending balance	699	1,088
Individually evaluated for impairment
Collectively evaluated for impairment			699	1,088
Balance	770	1,328	699	1,088
Other Consumer [Member]
Allowance for Credit Losses, beginning balance	140	160
Loans charged-off		(63)
Recoveries of loans previously charged-off	3	7
Net loans charged-off	3	(56)
Provision for credit losses	192	201
Allowance for Credit Losses, ending balance	335	305
Individually evaluated for impairment			80	50
Collectively evaluated for impairment			255	255
Balance	$ 140	$ 160	$ 335	$ 305

Amount of recovery of loans and lease receivables which had previously been fully or partially written-off as bad debts.

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Amount of other addition (reduction) in allowance reserve for credit loss.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 15
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Amount of loans and leases that have been written off from both loan receivables and allowance reserve for credit loss.

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

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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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Amount of allowance to cover probable credit losses on loans and leases. Includes carryover of or adjustments to the allowance for loan losses in connection with business combinations. Excludes allowance for loans and leases covered under loss sharing agreements.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
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Amount of expense related to estimated loss from loan and lease transactions.

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