Condensed Financial Information (Parent Company Only) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended																							12 Months Ended
	Dec. 31, 2012	Sep. 30, 2012		Jun. 30, 2012		Mar. 31, 2012		Dec. 31, 2011		Sep. 30, 2011		Jun. 30, 2011		Mar. 31, 2011		Dec. 31, 2010		Sep. 30, 2010		Jun. 30, 2010		Mar. 31, 2010		Dec. 31, 2012		Dec. 31, 2011		Dec. 31, 2010		Dec. 31, 2009
Equity in net assets of subsidiaries [Abstract]
Loans, net of allowance for loan losses of $19 and $19, respectively	$ 651,709							$ 693,303	[1]															$ 651,709		$ 693,303	[1]
Total assets	852,118							901,163	[1]							962,745	[1]							852,118		901,163	[1]	962,745	[1]
Subordinated debentures	24,119							24,119	[1]															24,119		24,119	[1]
Total Liabilities	743,122							794,698	[1]															743,122		794,698	[1]
Stockholders' equity	108,996							106,465	[1]							106,302	[1]							108,996		106,465	[1]	106,302	[1]	106,231
Total liabilities and stockholders' equity	852,118							901,163	[1]							962,745	[1]							852,118		901,163	[1]	962,745	[1]
Loans, allowance for loan losses	17,478							25,938	[1]															17,478		25,938	[1]
Statements of Operations [Abstract]
Interest income	9,412	9,104	[1]	10,276	[1]	10,265	[1]	10,558	[1]	10,991	[1]	11,254	[1]	11,698	[1]	11,809	[1]	12,083	[1]	13,045	[1]	12,596	[1]	39,057		44,501	[1]	49,533	[1]
Net interest income	6,825	6,077	[1]	6,940	[1]	6,713	[1]	6,899	[1]	7,135	[1]	7,308	[1]	7,572	[1]	7,361	[1]	7,177	[1]	8,050	[1]	7,616	[1]	26,555		28,914	[1]	30,204	[1]
Income before income tax provision	2,188	1,155	[1]	2,043	[1]	1,000	[1]	2,026	[1]	1,113	[1]	(1,251)	[1]	874	[1]	1,189	[1]	954	[1]	1,121	[1]	(733)	[1]	6,386		2,762	[1]	2,531	[1]
Income tax (expense) benefit	(914)	(481)	[1]	(840)	[1]	(423)	[1]	(860)	[1]	(467)	[1]	495	[1]	(378)	[1]	(529)	[1]	(418)	[1]	(488)	[1]	263	[1]	(2,658)		(1,210)	[1]	(1,172)	[1]
Net income	1,274	674	[1]	1,203	[1]	577	[1]	1,166	[1]	646	[1]	(756)	[1]	496	[1]	660	[1]	536	[1]	633	[1]	(470)	[1]	3,728		1,552	[1]	1,359	[1]
Cash Flows from Operating Activities [Abstract]
Net income	1,274	674	[1]	1,203	[1]	577	[1]	1,166	[1]	646	[1]	(756)	[1]	496	[1]	660	[1]	536	[1]	633	[1]	(470)	[1]	3,728		1,552	[1]	1,359	[1]
Adjustments to reconcile net income to net cash provided by (used in) operating activities:
Stock-based compensation expense																								43		61	[1]	162	[1]
Net cash provided by operating activities																								6,660		13,322	[1]	17,733	[1]
Cash Flows from Investing Activities [Abstract]
Net decrease in loans																								28,583		66,071	[1]	6,879	[1]
Net cash provided by investing activities																								53,945		66,582	[1]	8,824	[1]
Cash Flows from Financing Activities [Abstract]
Cash used in financing activities																								(54,603)		(63,469)	[1]	(7,003)	[1]
Increase (decrease) in cash and cash equivalents																								6,002		16,435	[1]	19,554	[1]
Cash and cash equivalents at beginning of year						87,390	[1]							70,955	[1]							51,401	[1]	87,390	[1]	70,955	[1]	51,401	[1]
Cash and cash equivalents at end of year	93,392							87,390	[1]							70,955	[1]							93,392		87,390	[1]	70,955	[1]
Severn Bancorp, Inc [Member]
Statements of Financial Condition [Abstract]
Cash	1,365							1,346	[1]															1,365		1,346	[1]
Equity in net assets of subsidiaries [Abstract]
Bank	127,366							122,676	[1]															127,366		122,676	[1]
Non-Bank	3,652							4,728	[1]															3,652		4,728	[1]
Loans, net of allowance for loan losses of $19 and $19, respectively	581							607	[1]															581		607	[1]
Other assets	1,414							1,341	[1]															1,414		1,341	[1]
Total assets	134,378							130,698	[1]															134,378		130,698	[1]
Subordinated debentures	24,119							24,119	[1]															24,119		24,119	[1]
Other liabilities	1,263							114	[1]															1,263		114	[1]
Total Liabilities	25,382							24,233	[1]															25,382		24,233	[1]
Stockholders' equity	108,996							106,465	[1]															108,996		106,465	[1]
Total liabilities and stockholders' equity	134,378							130,698	[1]															134,378		130,698	[1]
Loans, allowance for loan losses	19							19																19		19
Statements of Operations [Abstract]
Interest income																								43		82	[1]	65	[1]
Interest expense on subordinated debentures																								818		772	[1]	899	[1]
Net interest income																								(775)		(690)	[1]	(834)	[1]
Dividends received from subsidiaries																								0		0	[1]	0	[1]
General and administrative expenses																								205		13	[1]	386	[1]
Income before income tax provision																								(980)		(703)	[1]	(1,220)	[1]
Income tax (expense) benefit																								98		(55)	[1]	528	[1]
Equity in undistributed (earnings) loss of subsidiaries																								4,610		2,310	[1]	2,051	[1]
Net income																								3,728		1,552	[1]	1,359	[1]
Cash Flows from Operating Activities [Abstract]
Net income																								3,728		1,552	[1]	1,359	[1]
Adjustments to reconcile net income to net cash provided by (used in) operating activities:
Equity in undistributed (earnings) loss of subsidiaries																								(4,610)		(2,310)	[1]	(2,051)	[1]
(Increase) decrease in other assets																								(73)		290	[1]	(314)	[1]
Stock-based compensation expense																								43		61	[1]	162	[1]
Increase in other liabilities																								1,145		6	[1]	0	[1]
Net cash provided by operating activities																								233		(401)	[1]	(844)	[1]
Cash Flows from Investing Activities [Abstract]
Net decrease in loans																								26		340	[1]	0	[1]
Contribution from subsidiaries																								1,000		1,000	[1]	0	[1]
Net cash provided by investing activities																								1,026		1,340	[1]	0	[1]
Cash Flows from Financing Activities [Abstract]
Dividends paid on common stock																								0		0	[1]	0	[1]
Cash used in financing activities																								(1,240)		(1,450)	[1]	(1,450)	[1]
Increase (decrease) in cash and cash equivalents																								19		(511)	[1]	(2,294)	[1]
Cash and cash equivalents at beginning of year						1,346	[1]							1,857	[1]							4,151	[1]	1,346	[1]	1,857	[1]	4,151	[1]
Cash and cash equivalents at end of year	1,365							1,346	[1]							1,857	[1]							1,365		1,346	[1]	1,857	[1]
Series A Preferred Stock [Member]
Cash Flows from Financing Activities [Abstract]
Preferred stock dividend paid																								70		280	[1]	280	[1]
Series A Preferred Stock [Member] | Severn Bancorp, Inc [Member]
Cash Flows from Financing Activities [Abstract]
Preferred stock dividend paid																								(70)		(280)	[1]	(280)	[1]
Series B Preferred Stock [Member]
Cash Flows from Financing Activities [Abstract]
Preferred stock dividend paid																								293		1,170	[1]	1,170	[1]
Series B Preferred Stock [Member] | Severn Bancorp, Inc [Member]
Cash Flows from Financing Activities [Abstract]
Preferred stock dividend paid																								$ (1,170)		$ (1,170)	[1]	$ (1,170)	[1]

[1] Restated