AVAILABLE-FOR-SALE INVESTMENT SECURITIES (Details 5) - USD ($) $ in Thousands	Sep. 30, 2015	Dec. 31, 2014
Amortized Cost
Due within one year	$ 672,392
Due after one year through five years	994,971
Due after five years through ten years	339,821
Due after ten years	930,129
Total available-for-sale investment securities	2,937,313
Fair Value
Due within one year	672,656
Due after one year through five years	1,000,431
Due after five years through ten years	339,094
Due after ten years	940,096
Total available-for-sale investment securities	2,952,277	$ 2,626,617
Par value of securities pledged to secure public deposits	$ 970,000	$ 1,930,000