LOANS AND ALLOWANCE FOR LOAN AND LEASE LOSSES - PCI RECONCILIATION OF LOANS (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2015	Dec. 31, 2014
Disclosures on loans acquired
Carrying value of loans				$ 3,326,610	$ 3,040,495
PCI loan
Disclosures on loans acquired
Contractually-required principal				18,250	26,571
Non-accretable amount				(1,582)	(6,784)
Accretable amount	$ (2,297)	$ (3,457)	$ (3,095)	(4,125)	(2,297)
Carrying value of loans				$ 12,543	$ 17,490
Rollforward of the accretable discount on purchased loans within the scope of ASC Topic 310-30
Balance at the beginning of the period	(2,297)	(3,457)	(3,095)
Transfers between non-accretable and accretable	(4,055)	(3,783)	(6,455)
Net accretion into interest income on loans, including loan fees	2,227	4,943	6,093
Balance at the end of the period	$ (4,125)	$ (2,297)	$ (3,457)