LOAN SERVICING - Activity in SBA-Guaranteed Loan Servicing Asset (Detail) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2019	Mar. 31, 2018	Dec. 31, 2018
Servicing Assets at Fair Value [Line Items]
Service charges	$ 30.0	$ 30.0
SBA-Guaranteed Loan Servicing [Member]
Servicing Assets at Fair Value [Line Items]
SBA loans sold to investors with servicing retained	264.0		$ 283.0
SBA loans sold with servicing retained	6.0	12.0
Gain from sale of SBA loan, pretax	0.0	1.0
Service charges	1.0	1.0
Valuation allowance for servicing rights	0.8
Servicing Asset at Fair Value, Amount [Roll Forward]
Balance at beginning of period	4.0	5.0
Balance at end of period	4.0	5.0
Loan servicing rights, fair value, start	4.0	5.0
Loan servicing rights, fair value, end	$ 4.0	$ 5.0

Gain From Sale of Loan, Pretax

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- Definition

Loans Sold With Servicing Retained

+ References

No definition available.

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- Definition

Service Charges

+ References

No definition available.

+ Details

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- Definition

Unpaid Principal Balance For Loans Serviced For Investors

+ References

No definition available.

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- Definition

Amortized amount of contract to service financial assets under which the benefits of servicing are expected to more than adequately compensate the servicer.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
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-Publisher FASB
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- Definition

Fair value of an asset representing net future revenue from contractually specified servicing fees, late charges, and other ancillary revenues, in excess of future costs related to servicing arrangements.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 50
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-URI http://asc.fasb.org/extlink&oid=6469459&loc=d3e122501-111745

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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ References

No definition available.

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- Definition

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.

+ References

No definition available.

+ Details

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- Definition

Reflects the estimated amount of impairment as of the balance sheet date of recognized servicing assets that are being amortized in proportion to and over the period of estimated net servicing income or loss.

+ References

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