DEPOSITS (Composition of Deposits) (Detail) - USD ($) $ in Thousands	Mar. 31, 2018	Dec. 31, 2017
Disclosure Composition Of Deposits [Abstract]
Noninterest-bearing deposits	$ 1,767,523	$ 1,264,392
Interest-bearing deposits:
Demand	750,899	658,716
Money market savings	1,544,580	1,030,432
Regular savings	357,601	321,171
Time deposits of less than $100,000	378,428	293,201
Time deposits of $100,000 or more	828,175	395,750
Total interest-bearing deposits	3,859,683	2,699,270
Total deposits	$ 5,627,206	$ 3,963,662

Disclosure - Composition of Deposits [Abstract]

No definition available.

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- Definition

The amount of money in accounts that may bear interest and that the depositor is entitled to withdraw at any time without prior notice.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.12)
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

+ Details

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- Definition

The aggregate of all deposit liabilities held by the entity, including foreign and domestic, interest and noninterest bearing; may include demand deposits, saving deposits, Negotiable Order of Withdrawal (NOW) and time deposits among others.

+ References

+ Details

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- Definition

Amount of deposits in accounts that offer many of the same services as checking accounts although transactions may be somewhat more limited, share some of the characteristics of a money market fund and are insured by the Federal government, also known as money market accounts.

+ References

+ Details

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- Definition

Amount of interest bearing deposits with no stated maturity, which may include passbook and statement savings accounts and money-market deposit accounts (MMDAs).

+ References

+ Details

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- Definition

The aggregate of all domestic and foreign interest-bearing deposit liabilities.

+ References

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- References

No definition available.

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- Definition

The aggregate amount of all domestic and foreign noninterest-bearing deposits liabilities held by the entity.

+ References

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- Definition

Amount of time deposit liabilities, including certificates of deposit, in denominations of $100,000 or more.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Industry Guide
-Number 3
-Section V
-Paragraph D-E

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- Definition

Amount of time deposit liabilities, including certificates of deposit, in denominations of less than $100,000.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Industry Guide
-Number 3
-Section V
-Paragraph D-E

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