Loans and Allowance for Credit Losses (Details 1) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2017	Dec. 31, 2016
Allowance for Credit Losses, beginning balance	$ 59,074	$ 52,687
Loans charged-off	(4,575)	(6,340)
Recoveries of loans previously charged-off	1,288	1,396
Net loans charged-off	(3,287)	(4,944)
Provision for credit losses	8,971	11,331
Allowance for Credit Losses, ending balance	64,758	59,074
Individually evaluated for impairment			$ 7,601	$ 5,599
Collectively evaluated for impairment			57,157	53,475
Balance	64,758	59,074	64,758	59,074
Commercial [Member]
Allowance for Credit Losses, beginning balance	14,700	11,563
Loans charged-off	(747)	(3,745)
Recoveries of loans previously charged-off	681	220
Net loans charged-off	(66)	(3,525)
Provision for credit losses	(1,532)	6,662
Allowance for Credit Losses, ending balance	13,102	14,700
Individually evaluated for impairment			3,259	2,671
Collectively evaluated for impairment			9,843	12,029
Balance	13,102	14,700	13,102	14,700
Income Producing - Commercial Real Estate [Member]
Allowance for Credit Losses, beginning balance	21,105	14,122
Loans charged-off	(1,470)	(2,341)
Recoveries of loans previously charged-off	80	908
Net loans charged-off	(1,390)	(1,433)
Provision for credit losses	5,661	8,416
Allowance for Credit Losses, ending balance	25,376	21,105
Individually evaluated for impairment			2,380	1,943
Collectively evaluated for impairment			22,996	19,162
Balance	25,376	21,105	25,376	21,105
Owner Occupied - Commercial Real Estate - [Member]
Allowance for Credit Losses, beginning balance	4,010	3,279
Recoveries of loans previously charged-off	3	3
Net loans charged-off	3	3
Provision for credit losses	1,921	728
Allowance for Credit Losses, ending balance	5,934	4,010
Individually evaluated for impairment			1,382	350
Collectively evaluated for impairment			4,552	3,660
Balance	5,934	4,010	5,934	4,010
Real Estate Mortgage - Residential [Member]
Allowance for Credit Losses, beginning balance	1,284	1,268
Recoveries of loans previously charged-off	6	7
Net loans charged-off	6	7
Provision for credit losses	(346)	9
Allowance for Credit Losses, ending balance	944	1,284
Collectively evaluated for impairment			944	1,284
Balance	944	1,284	944	1,284
Construction - Commercial And Residencial [Member]
Allowance for Credit Losses, beginning balance	16,487	21,088
Loans charged-off	(2,158)
Recoveries of loans previously charged-off	492	215
Net loans charged-off	(1,666)	215
Provision for credit losses	3,671	(4,816)
Allowance for Credit Losses, ending balance	18,492	16,487
Individually evaluated for impairment			500	522
Collectively evaluated for impairment			17,992	15,965
Balance	16,487	16,487	18,492	16,487
Home Equity [Member]
Allowance for Credit Losses, beginning balance	1,328	1,292
Loans charged-off	(100)	(217)
Recoveries of loans previously charged-off	5	12
Net loans charged-off	(95)	(205)
Provision for credit losses	(463)	241
Allowance for Credit Losses, ending balance	770	1,328
Collectively evaluated for impairment			770	1,328
Balance	770	1,328	770	1,328
Other Consumer [Member]
Allowance for Credit Losses, beginning balance	160	75
Loans charged-off	(100)	(37)
Recoveries of loans previously charged-off	21	31
Net loans charged-off	(79)	(6)
Provision for credit losses	59	91
Allowance for Credit Losses, ending balance	140	160
Individually evaluated for impairment			80	113
Collectively evaluated for impairment			60	47
Balance	$ 140	$ 160	$ 140	$ 160