CONDENSED CONSOLIDATED STATEMENTS OF SHAREHOLDERS' EQUITY (Unaudited) - USD ($) $ in Thousands	Preferred Stock [Member]	Common Stock [Member]	Additional Paid-In Capital [Member]	Retained Earnings [Member]	Accumulated Other Comprehensive Income [Member]	Unearned Stock Grant Compensation [Member]	Treasury Stock [Member]	Total
Beginning Balance at Dec. 31, 2016	$ 55	$ 22,401	$ 57,114	$ 27,272	$ 5,830	$ (428)	$ (6,738)	$ 105,506
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net loss	0	0	0	(221)	0	0	0	(221)
Other comprehensive income (loss), net of tax	0	0	0	0	2,184	0	0	2,184
Dividends declared on common stock	0	0	0	(408)	0	0	0	(408)
Dividends accrued on preferred stock	0	0	0	(99)	0	0	0	(99)
Amortization of unearned compensation	0	0	0	0	0	116	0	116
Purchase of shares for treasury	0	0	0	0	0	0	(105)	(105)
Issuance of shares under stock plans	0	0	5	0	0	0	3	8
Ending Balance at Mar. 31, 2017	55	22,401	57,119	26,544	8,014	(312)	(6,840)	106,981
Beginning Balance at Dec. 31, 2017	55	22,401	57,495	30,993	9,751	(579)	(7,133)	112,983
Cumulative effect of adoption of updated accounting guidance for equity financial instruments at January 1, 2018 (ASU 2016-01 [Member]) at Dec. 31, 2017	0	0	0	9,825	(9,825)	0	0	0
Reclassification of certain tax effects from accumulated other comprehensive income at January 1, 2018 (ASU 2018-02 [Member]) at Dec. 31, 2017	0	0	0	(2,100)	2,100	0	0	0
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net loss	0	0	0	(5,024)	0	0	0	(5,024)
Other comprehensive income (loss), net of tax	0	0	0	0	(5,644)	0	0	(5,644)
Dividends declared on common stock	0	0	0	(407)	0	0	0	(407)
Dividends accrued on preferred stock	0	0	0	(99)	0	0	0	(99)
Restricted stock grants	0	0	(68)	0	0	115	(47)	0
Amortization of unearned compensation	0	0	0	0	0	77	0	77
Purchase of shares for treasury	0	0	0	0	0	0	(169)	(169)
Issuance of shares under stock plans	0	0	4	0	0	0	3	7
Ending Balance at Mar. 31, 2018	$ 55	$ 22,401	$ 57,431	$ 33,188	$ (3,618)	$ (387)	$ (7,346)	$ 101,724