Condensed Consolidated Balance Sheets (Unaudited) (Parenthetical) (USD $) In Thousands, except Share data, unless otherwise specified	Mar. 31, 2014	Dec. 31, 2013
Investment securities:
Held-to-maturity, at amortized cost	$ 0	$ 0
Stockholders Equity
Convertible preferred stock, no par value (in dollars per share)	$ 0	$ 0
Convertible preferred stock, authorized (in shares)	1,000,000	1,000,000
Convertible preferred stock, issued (in shares)	10,426	10,427
Common stock, par value (in dollars per share)	$ 4	$ 4
Common stock, authorized (in shares)	18,000,000	18,000,000
Common stock, issued (in shares)	7,820,360	7,797,597
Treasury stock (in shares)	1,954,922	1,913,817