Segment Information (Narrative) (Details) (USD $) In Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2011	Jun. 30, 2010	Jun. 30, 2011	Jun. 30, 2010
Net interest income	$ 62,319	$ 55,154	$ 123,686	$ 110,271
Noninterest expense	79,758	77,871	159,683	154,931
Monroe Bancorp [Member] | Community Banking [Member]
Net interest income	10,900		19,100
Community Banking [Member]
Net interest income	73,975	62,088	143,064	123,813
Noninterest expense	69,066	58,755	131,243	118,783
Monroe Bancorp [Member]
Net interest income	(57,791)	(66,100)	(117,572)	(129,347)
Noninterest expense	$ 7,000		$ 14,900