Loans and Allowance for Loan Losses, Troubled Debt Restructurings (Details)	12 Months Ended
	Dec. 31, 2016 USD ($) Contract	Dec. 31, 2015 USD ($) Contract	Dec. 31, 2014 USD ($) Contract
Troubled debt restructuring categorized by loan classification [Abstract]
Number of contracts | Contract	6	2	12
Pre Modification Outstanding Recorded Investment	$ 11,084,000	$ 657,000	$ 4,111,000
Post Modification Outstanding Recorded Investment net of related allowance	$ 11,083,000	$ 522,000	$ 3,087,000
Percentage of credit exposure to risk based capital	25.00%
Commercial Real Estate - Mortgage [Member]
Troubled debt restructuring categorized by loan classification [Abstract]
Number of contracts | Contract	0	1	0
Pre Modification Outstanding Recorded Investment	$ 0	$ 223,000	$ 0
Post Modification Outstanding Recorded Investment net of related allowance	$ 0	$ 185,000	$ 0
Consumer Real Estate - Mortgage [Member]
Troubled debt restructuring categorized by loan classification [Abstract]
Number of contracts | Contract	0	0	1
Pre Modification Outstanding Recorded Investment	$ 0	$ 0	$ 47,000
Post Modification Outstanding Recorded Investment net of related allowance	$ 0	$ 0	$ 38,000
Construction and Land Development [Member]
Troubled debt restructuring categorized by loan classification [Abstract]
Number of contracts | Contract	0	0	1
Pre Modification Outstanding Recorded Investment	$ 0	$ 0	$ 436,000
Post Modification Outstanding Recorded Investment net of related allowance	$ 0	$ 0	$ 403,000
Commercial and Industrial [Member]
Troubled debt restructuring categorized by loan classification [Abstract]
Number of contracts | Contract	6	1	10
Pre Modification Outstanding Recorded Investment	$ 11,084,000	$ 434,000	$ 3,628,000
Post Modification Outstanding Recorded Investment net of related allowance	$ 11,083,000	$ 337,000	$ 2,646,000
Number of Contracts of troubled debt restructurings subsequently defaulted | Contract	0	0	0
Troubled debt restructurings subsequently defaulted	$ 0	$ 0	$ 0
Consumer and Other [Member]
Troubled debt restructuring categorized by loan classification [Abstract]
Number of contracts | Contract	0	0	0
Pre Modification Outstanding Recorded Investment	$ 0	$ 0	$ 0
Post Modification Outstanding Recorded Investment net of related allowance	0	0	$ 0
Lessors of Nonresidential Buildings [Member]
Loan portfolio credit risk exposure [Abstract]
Financing receivables principal balance	1,294,366,000
Financing receivables unfunded commitment	407,487,000
Financing receivables exposure	1,701,853,000	1,078,211,000
Lessors of Residential Buildings [Member]
Loan portfolio credit risk exposure [Abstract]
Financing receivables principal balance	526,259,000
Financing receivables unfunded commitment	347,975,000
Financing receivables exposure	874,234,000	500,266,000
New Housing Operative Builders [Member]
Loan portfolio credit risk exposure [Abstract]
Financing receivables principal balance	229,035,000
Financing receivables unfunded commitment	157,370,000
Financing receivables exposure	386,405,000	206,539,000
Hotels and Motels [Member]
Loan portfolio credit risk exposure [Abstract]
Financing receivables principal balance	127,296,000
Financing receivables unfunded commitment	164,569,000
Financing receivables exposure	$ 291,865,000	$ 167,317,000