Consolidated Statement of Shareholders' Equity (unaudited) - USD ($) $ in Thousands	Total	Preferred Stock	Common Stock	Additional Paid-in Capital	Unearned ESOP Shares	Accumulated Other Comprehensive Loss	Retained Earnings
Beginning balance (in shares) at Dec. 31, 2016		123,098	11,362,716
Beginning balance at Dec. 31, 2016	$ 214,376	$ 41,110	$ 1,136	$ 111,166	$ (1,233)	$ (1,010)	$ 63,207
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net loss	(1,257)						(1,257)
Dividends on Series B and Series C preferred stock	(2,432)						(2,432)
Dividends on common stock	(2,645)						(2,645)
Issuance of common stock (in shares)			5,100,034
Issuance of common stock	57,151		$ 510	56,641
Restricted stock grant (in shares)			58,090
Restricted stock grant	0		$ 6	(6)
Conversion of Series C preferred stock to common stock (in shares)		(1,223)	(6,791)
Conversion of Series C preferred stock to common stock	0	$ (123)	$ 1	122
ESOP shares released for allocation	316			50	266
Exercise of stock options (in shares)			20,498
Exercise of stock options	266		$ 2	264
Vested restricted stock (in shares)			700
Stock option and restricted stock compensation expense	85			85
Change in accumulated other comprehensive loss	1,783					1,783
Ending balance at Sep. 30, 2017	267,643	$ 40,987	$ 1,655	168,322	(967)	773	56,873
Ending balance (in shares) at Sep. 30, 2017		121,875	16,548,829
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Adoption of ASU 2016-01 | Accounting Standards Update 2016-01						31	(31)
Beginning balance (in shares) at Dec. 31, 2017		121,875	16,548,829
Beginning balance at Dec. 31, 2017	254,015	$ 40,987	$ 1,655	168,412	(937)	(1,828)	45,726
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net loss	(5,207)						(5,207)
Dividends on Series B and Series C preferred stock	(2,430)						(2,430)
Dividends on common stock	(496)						(496)
Restricted stock grant (in shares)			80,748
Restricted stock grant			$ 8	(8)
Restricted stock forfeitures (in shares)			(38,837)
Restricted stock forfeitures			$ (4)	4
Conversion of Series C preferred stock to common stock (in shares)		(150)	(833)
Conversion of Series C preferred stock to common stock		$ (15)		15
ESOP shares released for allocation	92				92
ESOP compensation expense	31			31
Exercise of stock options (in shares)			49,532
Exercise of stock options	642		$ 5	637
Stock option and restricted stock compensation expense	(21)			(21)
Change in accumulated other comprehensive loss	(5,175)					(5,175)
Ending balance at Sep. 30, 2018	$ 241,451	$ 40,972	$ 1,664	$ 169,070	$ (845)	$ (6,972)	$ 37,562
Ending balance (in shares) at Sep. 30, 2018		121,725	16,641,105