Consolidated Balance Sheets (Parenthetical) (USD $) In Thousands, except Share data, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014	Mar. 31, 2014
Securities, fair value	$ 550,194us-gaap_InvestmentsFairValueDisclosure	$ 524,861us-gaap_InvestmentsFairValueDisclosure	$ 587,100us-gaap_InvestmentsFairValueDisclosure
Common stock, par value	$ 1.00	$ 1.00	$ 1.00
Common stock, shares authorized	20,000,000us-gaap_CommonStockSharesAuthorized	20,000,000us-gaap_CommonStockSharesAuthorized	20,000,000us-gaap_CommonStockSharesAuthorized
Common stock, shares issued	15,512,545us-gaap_CommonStockSharesIssued	15,504,513us-gaap_CommonStockSharesIssued	15,363,728us-gaap_CommonStockSharesIssued
Common stock, shares outstanding	15,512,545us-gaap_CommonStockSharesOutstanding	15,504,513us-gaap_CommonStockSharesOutstanding	15,363,728us-gaap_CommonStockSharesOutstanding
Accumulated other comprehensive income, tax	$ 3,110	$ 2,644	$ 2,486
Senior Preferred Stock [Member]
Preferred stock, par value	$ 1.00	$ 1.00	$ 1.00
Preferred stock, shares authorized	10,000,000	10,000,000	10,000,000
Preferred stock, shares issued	0	0	0
Cumulative Preferred Stock [Member]
Preferred stock, par value	$ 5.00	$ 5.00	$ 5.00
Preferred stock, shares authorized	900,000	900,000	900,000
Preferred stock, shares issued	0	0	0

Face amount or stated value per share of common stock.

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