DERIVATIVES - Derivative Financial Instruments, Average Remaining Maturity and the Weighted-Average Interest Rates being Paid and Received (Detail) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017
Derivative [Line Items]
Notional Value	$ 2,719,980	$ 1,674,080
Asset conversion swaps
Derivative [Line Items]
Notional Value	$ 2,719,980
Average Maturity (years)	6 years 2 months
Fair Value	$ 1
Weighted-Average Rate Receive	4.68%
Weighted-Average Rate Pay	4.68%
Asset conversion swaps \| Derivative Financial Instruments Receive Fixed Pay Variable
Derivative [Line Items]
Notional Value	$ 1,359,990
Average Maturity (years)	6 years 2 months
Fair Value	$ 5,615
Weighted-Average Rate Receive	4.70%
Weighted-Average Rate Pay	4.67%
Asset conversion swaps \| Derivative Financial Instruments Receive Variable Pay Fixed
Derivative [Line Items]
Notional Value	$ 1,359,990
Average Maturity (years)	6 years 2 months
Fair Value	$ (5,614)
Weighted-Average Rate Receive	4.67%
Weighted-Average Rate Pay	4.70%

Aggregate notional amount specified by the derivative(s). Expressed as an absolute value.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Article 12
-Section 13
-Sentence Column B

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- Definition

Fair values as of the balance sheet date of the net amount of all assets and liabilities resulting from contracts that meet the criteria of being accounted for as derivative instruments.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 45
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=6945355&loc=d3e41228-113958

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- Definition

Average fixed interest rate related to the group of interest rate derivatives.

+ References

No definition available.

+ Details

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- Definition

Average remaining period until maturity of the derivative contract, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

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- Definition

Average variable interest rate related to the group of interest rate derivatives.

+ 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.

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