Exception Report, Decrease in FICO Score, Percent

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Loans and Leases Receivable, Net Of Deferred Income, Increase (Decrease) in Period

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Loans and Leases Receivable, Net Of Deferred Income, Percentage Increase (Decrease) in Period

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Mortgage Loans on Real Estate, Periodic Payment Terms, Balloon Payment Period

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

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Amount before allowance and after deduction of deferred interest and fees, unamortized costs and premiums and discounts from face amounts, of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Excludes loans and leases covered under loss sharing agreements.

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LOANS AND LEASES AND ALLOWANCE FOR LOAN AND LEASE LOSSES - Non Traditional Mortgage Loans Additional Information (Details) - USD ($)	6 Months Ended	12 Months Ended
	Jun. 30, 2017	Dec. 31, 2016	Jun. 30, 2016
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	$ 5,956,337,000	$ 6,034,752,000	$ 6,236,115,000
Percentage decrease in credit score to run exception report	10.00%
Non-Traditional Mortgages (NTM)
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	$ 773,037,000	885,148,000
Consumer \| Non-Traditional Mortgages (NTM)
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	773,037,000	885,148,000
Increase (decrease) in loans receivable	$ (112,100,000)
Increase (decrease) in loans receivable, percentage	(12.70%)
Consumer \| Non-Traditional Mortgages (NTM) \| Green Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	$ 86,000,000	91,000,000
Interest only notes balloon payment period	15 years
Consumer \| Non-Traditional Mortgages (NTM) \| Green Loans \| Nonperforming Financing Receivable
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	$ 0	0
Consumer \| Non-Traditional Mortgages (NTM) \| Interest Only Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	683,200,000	784,400,000
Consumer \| Non-Traditional Mortgages (NTM) \| Interest Only Loans \| Nonperforming Financing Receivable
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	0	467,000
Consumer \| Non-Traditional Mortgages (NTM) \| Negative amortization
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	3,800,000	9,800,000
Consumer \| Non-Traditional Mortgages (NTM) \| Negative amortization \| Nonperforming Financing Receivable
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	$ 0	$ 0
Consumer \| Non-Traditional Mortgages (NTM) \| Loan Portfolio \| Loan Portfolio Concentration Risk
Accounts, Notes, Loans and Financing Receivable [Line Items]
Concentration risk percentage	13.00%	14.70%