LOANS, LEASES & ALLOWANCE FOR LOAN AND LEASE LOSSES - ALLOWANCE FOR CREDIT LOSS NARRATIVE (Details) - Multifamily real estate secured $ in Millions	Jun. 30, 2019 USD ($)
Financing Receivable, Allowance for Credit Loss [Line Items]
Interest only loans	$ 1,300.0
Option adjustable-rate mortgage loans	$ 1.6

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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