DEPOSITS - Summary of Deposit Balances (Detail) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014
Deposits [Line Items]
Non-interest bearing checking accounts	$ 1,175,943	$ 900,616
Savings accounts	2,641,793us-gaap_DepositsSavingsDeposits	2,450,484us-gaap_DepositsSavingsDeposits
Interest-bearing checking accounts	1,127,560	1,054,136
Certificates of deposit	2,323,259	2,191,663
Brokered certificates of deposit	2,572,483	2,887,046
Total deposits	$ 9,841,038us-gaap_Deposits	$ 9,483,945us-gaap_Deposits

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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

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

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 12

-Article 9

+ 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).

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+ Details

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- Definition

Amount of interest-bearing domestic third-party deposits placed by or through the assistance of a deposit broker, also known as brokered deposit liabilities.

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+ Details

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- Definition

Amount of interest-bearing domestic certificate of deposit liabilities.

+ References

+ Details

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- Definition

Amount of interest-bearing domestic checking deposit liabilities.

+ References

+ Details

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- Definition

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

+ References

+ Details

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