OTHER BORROWINGS - Components of Other Borrowings (Parenthetical) (Detail) - Junior Subordinated Debt [Member]	3 Months Ended
Mar. 31, 2019	Dec. 31, 2018
due June 17, 2034 [Member]
Subordinated Borrowing [Line Items]
Floating Interest rate on junior subordinated debentures	5.36%	5.54%
Callable step-rate notes rate	2.75%
Subordinated Borrowing Due Date	Jun. 17, 2034
due June 17, 2034 [Member] \| London Interbank Offered Rate (LIBOR) [Member]
Subordinated Borrowing [Line Items]
Debt Instrument Description Of Variable Rate Basis	3-month LIBOR
due September 20, 2034 [Member]
Subordinated Borrowing [Line Items]
Floating Interest rate on junior subordinated debentures	5.13%	5.29%
Callable step-rate notes rate	2.50%
Subordinated Borrowing Due Date	Sep. 20, 2034
due September 20, 2034 [Member] \| London Interbank Offered Rate (LIBOR) [Member]
Subordinated Borrowing [Line Items]
Debt Instrument Description Of Variable Rate Basis	3-month LIBOR

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

No definition available.

Name:	us-gaap_DebtInstrumentBasisSpreadOnVariableRate1
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

The reference rate for the variable rate of the debt instrument, such as LIBOR or the US Treasury rate and the maturity of the reference rate used, such as three months or six months LIBOR.

+ References

No definition available.

+ Details

Name:	us-gaap_DebtInstrumentDescriptionOfVariableRateBasis
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

The interest rate applicable to the portion of the carrying amount of long-term borrowings outstanding as of the balance sheet date, including current maturities, which accrues interest at a rate subject to change from time to time.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.22(a)(1))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

Name:	us-gaap_LongTermDebtPercentageBearingVariableInterestRate
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Date the payments are due on subordinated debt, in CCYY-MM-DD format.

+ References

No definition available.

+ Details

Name:	us-gaap_SubordinatedBorrowingDueDate
Namespace Prefix:	us-gaap_
Data Type:	xbrli:dateItemType
Balance Type:	na
Period Type:	duration

- 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

Name:	us-gaap_SubordinatedBorrowingLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Details

Name:	us-gaap_LongtermDebtTypeAxis=us-gaap_JuniorSubordinatedDebtMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DebtInstrumentRedemptionPeriodAxis=us-gaap_DebtInstrumentRedemptionPeriodOneMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_VariableRateAxis=us-gaap_LondonInterbankOfferedRateLIBORMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DebtInstrumentRedemptionPeriodAxis=us-gaap_DebtInstrumentRedemptionPeriodTwoMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: