Borrowings (Trust Preferred Securities) (Narrative) (Details) $ in Millions						1 Months Ended	12 Months Ended
	Dec. 23, 2015 AUD ($)	May 01, 2012	Apr. 30, 2009 USD ($)	Dec. 31, 2008 USD ($)	Feb. 05, 2007 USD ($)	Dec. 31, 2011 USD ($)	Dec. 31, 2017 USD ($)	Dec. 31, 2016 USD ($)	Dec. 31, 2015 USD ($)	Dec. 31, 2009 USD ($)	Dec. 31, 2008 USD ($)	Dec. 31, 2014 USD ($)	Mar. 31, 2009 USD ($)
Debt Instrument [Line Items]
Trust preferred securities issued					$ 51,500,000
Trust preferred securities issued to third party					50,000,000
Trust preferred securities issued to parent					1,500,000
Investment in common trust securities					1,500,000		$ 838,000	$ 838,000
Trust preferred dividends paid							1,400,000	1,400,000	$ 1,400,000
Preferred stock dividends payable							$ 250,000	$ 184,000
Marketable securities													$ 11,500,000
Amortization of debt discount	$ 2.0
Trust Preferred Securities [Member]
Debt Instrument [Line Items]
Trust preferred securities					$ 51,500,000								$ 22,900,000
Debt instrument term					20 years
Initial interest rate		9.22%
Period of initial interest rate		5 years
LIBOR period		3 months
Spread over LIBOR		4.00%
Maturity date							Apr. 30, 2027	Apr. 30, 2027
Principal payment							$ 0
Initial period of payoff restriction							5 years
Percentage of principal that may be paid without penalty after initial restriction period							100.00%
Period of waiver on all financial covenants											9 years
Financial covenant waiver payment due				$ 1,600,000							$ 1,600,000	$ 270,000
Financial covenant waiver payment				$ 1,100,000		$ 270,000
Frequency of interest payment							3 months
Extinguishment of debt			$ 22,900,000
Amortization of debt discount										$ 106,000
Gain on retirement of subordinated debt			10,700,000
Write-off of deferred loan costs			$ 749,000