5. FAIR VALUE MEASUREMENTS - Available-for-sale securities on recurring basis (Details) (USD $) In Thousands, unless otherwise specified	Jun. 30, 2014	Dec. 31, 2013
Available-for-sale securities	$ 213,696	$ 279,479
Obligations of U.S. government sponsored agencies
Available-for-sale securities		18,198
Level 1
Available-for-sale securities	0	0
Level 2
Available-for-sale securities	213,696	279,479
Level 3
Available-for-sale securities	0	0
Level 1
Available-for-sale securities	0	0
Level 2
Available-for-sale securities	213,696	279,479
Level 3
Available-for-sale securities	0	0
Obligations of states and political subdivisions
Available-for-sale securities	4,724	5,317
Obligations of states and political subdivisions | Level 1
Available-for-sale securities	0	0
Obligations of states and political subdivisions | Level 2
Available-for-sale securities	4,724	5,317
Obligations of states and political subdivisions | Level 3
Available-for-sale securities	0	0
Mortgage-backed securities
Available-for-sale securities	200,845	248,277
Mortgage-backed securities | Level 1
Available-for-sale securities	0	0
Mortgage-backed securities | Level 2
Available-for-sale securities	200,845	248,277
Mortgage-backed securities | Level 3
Available-for-sale securities	0	0
Corporate bonds
Available-for-sale securities	5,145	4,755
Corporate bonds | Level 1
Available-for-sale securities	0	0
Corporate bonds | Level 2
Available-for-sale securities	5,145	4,755
Corporate bonds | Level 3
Available-for-sale securities	0	0
Equity securities
Available-for-sale securities	2,982	2,932
Equity securities | Level 1
Available-for-sale securities	0	0
Equity securities | Level 2
Available-for-sale securities	2,982	2,932
Equity securities | Level 3
Available-for-sale securities	0	0
Obligations of U.S. government sponsored agencies | Level 1
Available-for-sale securities		0
Obligations of U.S. government sponsored agencies | Level 2
Available-for-sale securities		18,198
Obligations of U.S. government sponsored agencies | Level 3
Available-for-sale securities		$ 0