LOANS AND LEASES AND ALLOWANCE FOR LOAN AND LEASE LOSSES - Credit Quality Indicators and Purchased Credit Impaired Loans Additional Information (Details) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2016 USD ($) bulk_loan_acquisition	Sep. 30, 2015 USD ($) bulk_loan_acquisition	Sep. 30, 2016 USD ($) bulk_loan_acquisition	Sep. 30, 2015 USD ($) bulk_loan_acquisition
Receivables [Abstract]
Loans delinquent			60 days
Number of bulk acquisitions | bulk_loan_acquisition	1	2	0	3
Unpaid principal balance on loan acquisition	$ 103.8	$ 145.5	$ 0.0	$ 228.0
Fair value of loan acquisition	91.0	138.8	0.0	218.6
Unpaid principal balance with credit quality deterioration at acquisition		145.5		177.1
Fair value with credit quality deterioration at acquisition		138.8		169.1
Unpaid principle balances of PCI loans sold	98.3	40.9	98.3	40.9
Carrying value of loans sold	82.4	25.0	82.4	25.0
Gain on PCI loans sold	$ 4.4	$ 5.9	$ 4.4	$ 5.9