INTEREST-BEARING DEPOSITS AND SECURITIES (Schedule of Investments) (Details) (USD $) In Thousands, unless otherwise specified	Sep. 30, 2013	Dec. 31, 2012	Sep. 30, 2012
Open Option Contracts Written [Line Items]
Interest-bearing deposits included in cash and due from banks	$ 106,625	$ 114,928	$ 143,251
Interest-bearing deposits and marketable securities	780,172	782,237	801,466
Total securities [Member]
Open Option Contracts Written [Line Items]
Marketable securities	637,839	630,604	621,177
U.S. Government and agency obligations [Member]
Open Option Contracts Written [Line Items]
Marketable securities	61,473	98,617	159,885
Total municipal bonds [Member]
Open Option Contracts Written [Line Items]
Marketable securities	151,834	135,025	132,913
Taxable municipal bonds [Member]
Open Option Contracts Written [Line Items]
Marketable securities	36,501	31,480	26,742
Tax exempt municipal bonds [Member]
Open Option Contracts Written [Line Items]
Marketable securities	115,333	103,545	106,171
Corporate bonds [Member]
Open Option Contracts Written [Line Items]
Marketable securities	46,145	48,519	40,505
Total mortgage-backed or related securities [Member]
Open Option Contracts Written [Line Items]
Marketable securities	353,070	305,864	255,072
1-4 residential agency guaranteed [Member]
Open Option Contracts Written [Line Items]
Marketable securities	58,616	105,770	108,830
1-4 residential other [Member]
Open Option Contracts Written [Line Items]
Marketable securities	1,100	1,299	1,412
Multifamily agency guaranteed [Member]
Open Option Contracts Written [Line Items]
Marketable securities	283,252	188,136	144,830
Multifamily other [Member]
Open Option Contracts Written [Line Items]
Marketable securities	10,102	10,659	0
Asset-backed Securities [Member]
Open Option Contracts Written [Line Items]
Marketable securities	25,249	42,516	32,752
SLMA [Member]
Open Option Contracts Written [Line Items]
Marketable securities	15,676	32,474	32,752
Other asset-backed securities [Member]
Open Option Contracts Written [Line Items]
Marketable securities	9,573	10,042	0
Equity securities (excludes FHLB stock) [Member]
Open Option Contracts Written [Line Items]
Marketable securities	68	63	50
FHLB stock [Member]
Open Option Contracts Written [Line Items]
Marketable securities	$ 35,708	$ 36,705	$ 37,038