ACQUISITIONS (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Nov. 10, 2016	Dec. 31, 2015	Feb. 20, 2015	Dec. 31, 2014
Assets
Goodwill	$ 221,526		$ 201,083		$ 170,421
Peoples Federal Bancshares, Inc [Member]
Assets
Cash				$ 41,957
Investments				43,585
Loans				463,927
Premises and equipment				9,346
Goodwill				30,662
Core deposit intangible				3,936
Other assets				46,920
Total assets acquired				640,333
Liabilities
Deposits				432,250
Borrowings				51,209
Other liabilities				15,054
Total liabilities assumed				498,513
Purchase price				$ 141,820
New England Bancorp, Inc. [Member]
Assets
Cash		$ 9,679
Loans		225,731
Premises and equipment		201
Goodwill		20,443
Core deposit intangible		670
Other assets		19,197
Total assets acquired		275,921
Liabilities
Deposits		175,686
Borrowings		51,150
Other liabilities		7,344
Total liabilities assumed	$ 234,180
Purchase price		$ 41,741