GOODWILL AND IDENTIFIABLE INTANGIBLE ASSETS (Details 1) (USD $) In Thousands, unless otherwise specified	3 Months Ended								12 Months Ended									12 Months Ended
	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2012	Sep. 30, 2012	Jun. 30, 2012	Mar. 31, 2012	Dec. 31, 2013		Dec. 31, 2012		Dec. 31, 2011		Dec. 31, 2013 Mayflower Bankcorp, Inc. [Member]	Dec. 31, 2011 Mayflower Bankcorp, Inc. [Member]	Nov. 15, 2013 Mayflower Bankcorp, Inc. [Member]	Dec. 31, 2012 Central Bankcorp, Inc. [Member]	Nov. 09, 2012 Central Bankcorp, Inc. [Member]
Goodwill [Roll Forward]
Balance at beginning of year				$ 150,391				$ 130,074	$ 150,391		$ 130,074		$ 129,617				$ 20,030		$ 22,544
Acquisitions															20,030			22,544
Impairment						(2,227)				[1]	(2,227)	[1]		[1]
Earn out payments from prior acquisitions													457
Balance at end of year	$ 170,421				$ 150,391				$ 170,421		$ 150,391		$ 130,074				$ 20,030		$ 22,544

[1] Amount represents the total amount of goodwill relating to Compass Exchange Advisors, LLC, which was acquired in January 2007.