FHLB Advances, Other Borrowings and Subordinated Notes (Summary of Pledged Securities Related to Securities Sold Under Repurchase Agreements) (Details) - Securities sold under repurchase agreements - USD ($) $ in Thousands	Sep. 30, 2018	Dec. 31, 2017	Sep. 30, 2017
Financial Instruments Owned and Pledged as Collateral [Line Items]
Pledged financial instruments	$ 35,900
Securities sold under agreements to repurchase	17,400	$ 17,200	$ 20,000
Overnight Sweep Collateral
Financial Instruments Owned and Pledged as Collateral [Line Items]
Pledged financial instruments	35,911
Excess collateral	18,480
Securities sold under agreements to repurchase	17,431
Overnight Sweep Collateral | Available-for-sale securities pledged | Mortgage-backed securities
Financial Instruments Owned and Pledged as Collateral [Line Items]
Pledged financial instruments	9,547
Overnight Sweep Collateral | Held-to-maturity securities pledged | U.S. Government agencies
Financial Instruments Owned and Pledged as Collateral [Line Items]
Pledged financial instruments	$ 26,364