INTEREST-BEARING DEPOSITS AND SECURITIES (Schedule of Investments) (Details) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014
Open Option Contracts Written [Line Items]
Interest-bearing deposits included in cash and due from banks	$ 215,114	$ 54,995
Securities	567,330	582,537
Interest-bearing deposits and securities	782,444	637,532
U.S. Government and agency obligations [Member]
Open Option Contracts Written [Line Items]
Securities	26,242	33,421
Total municipal bonds [Member]
Open Option Contracts Written [Line Items]
Securities	184,227	171,419
Taxable municipal bonds [Member]
Open Option Contracts Written [Line Items]
Securities	29,374	29,566
Tax exempt municipal bonds [Member]
Open Option Contracts Written [Line Items]
Securities	154,853	141,853
Corporate bonds [Member]
Open Option Contracts Written [Line Items]
Securities	24,297	25,936
Total mortgage-backed or related securities [Member]
Open Option Contracts Written [Line Items]
Securities	307,007	326,307
1-4 residential agency guaranteed [Member]
Open Option Contracts Written [Line Items]
Securities	57,966	58,825
1-4 residential other [Member]
Open Option Contracts Written [Line Items]
Securities	575	713
Multifamily agency guaranteed [Member]
Open Option Contracts Written [Line Items]
Securities	237,816	256,272
Multifamily other [Member]
Open Option Contracts Written [Line Items]
Securities	10,650	10,497
Asset-backed Securities [Member]
Open Option Contracts Written [Line Items]
Securities	25,500	25,395
Student Loan Marketing Association (SLMA) [Member]
Open Option Contracts Written [Line Items]
Securities	15,611	15,629
Other asset-backed securities [Member]
Open Option Contracts Written [Line Items]
Securities	9,889	9,766
Equity securities (excludes FHLB stock) [Member]
Open Option Contracts Written [Line Items]
Securities	$ 57	$ 59