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DERIVATIVE INSTRUMENTS AND HEDGING ACTIVITIES - Additional Information (Detail) - USD ($) | 6 Months Ended |
--- | --- | ---
Jun. 30, 2019 | Jun. 30, 2018 | Dec. 31, 2018
Derivative [Line Items] |  |  |
Notional amount | $ 8,202,000,000 |  | $ 6,942,000,000
Additional amount in excess of posted collateral required in case of breached agreements | $ 500,000 |  | 700,000
Interest rate contracts [Member] |  |  |
Derivative [Line Items] |  |  |
Maximum length of time hedged in interest rate cash flow hedge | 5 years 4 months 24 days |  |
Period to reclassification of cash flow hedge gain loss | 12 months |  |
Derivative gains to be reclassified within twelve months | $ 2,800,000 |  |
Derivative gains to be reclassified within twelve months, net of tax | 2,200,000 |  |
Derivative gain or loses excluded from assessment of hedge effectiveness | 0 |  |
Gains or losses from cash flow hedge derivatives reclassified to earnings | 0 | $ 0 |
Credit risk contracts - not designated [Member] |  |  |
Derivative [Line Items] |  |  |
Notional amount | 165,200,000 |  |
Maximum exposure under credit risk agreement assuming customer default | 300,000 |  | 100,000
Credit risk derivatives, purchased at fair value | 100,000 |  | 50,000.00
Credit risk derivatives, sold at fair value | $ (300,000) |  | $ 100,000
Credit risk contracts - not designated [Member] | Minimum [Member] |  |  |
Derivative [Line Items] |  |  |
Risk participation agreements, term | 3 months |  |
Credit risk contracts - not designated [Member] | Maximum [Member] |  |  |
Derivative [Line Items] |  |  |
Risk participation agreements, term | 9 years |  |

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- Definition The estimated gross amount of existing gains or losses on cash flow hedges at the reporting date expected to be reclassified to earnings within the next 12 months. + References No definition available. + Details
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- Definition Credit Risk Derivatives, Purchased at Fair Value + References No definition available. + Details
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- Definition Maximum exposure assuming a customer defaults on their obligation to perform under certain derivative swap contracts with third parties. + References No definition available. + Details
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- Definition Period of time during which net amount of existing gains or losses on cash flow hedges are expected to be reclassified to earnings. + References No definition available. + Details
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- Definition Aggregate notional amount specified by the derivative(s). Expressed as an absolute value. + References 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 + Details
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- Definition The aggregate fair value of additional assets that would be required to be posted as collateral for derivative instruments with credit-risk-related contingent features if the credit-risk-related contingent features were triggered at the end of the reporting period. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4H -Subparagraph (e) -URI http://asc.fasb.org/extlink&oid=109980867&loc=SL5624258-113959 + Details
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- Definition The effective portion of net gain (loss) reclassified from accumulated other comprehensive income into income on derivative instruments designated and qualifying as hedging instruments. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4D -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=109980867&loc=SL5624177-113959 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4C -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=109980867&loc=SL5624171-113959 + Details
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- Definition Period remaining until the derivative contract matures, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. + References No definition available. + Details
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- Definition Maximum period the entity is hedging its exposure to the variability in future cash flows for forecasted transactions, excluding those forecasted transactions related to the payment of variable interest on existing financial instruments, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 30 -Section 50 -Paragraph 1 -Subparagraph (d) -URI http://asc.fasb.org/extlink&oid=112277219&loc=d3e80748-113994 + Details
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