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

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Name Regulation S-X (SX)
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Notional maturities for all interest-rate contracts for the remainder of the fiscal year.

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Notional maturities for all interest-rate contracts during fiscal year four.

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Notional maturities for all interest-rate contracts during fiscal year six.

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Notional maturities for all interest-rate contracts during fiscal year three.

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Notional maturities for all interest-rate contracts during the next fiscal year (year two).

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Notional maturities for all interest-rate contracts maturing thereafter.

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The estimated net 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.

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Amount as of the balance sheet date of the unamortized adjustment to the carrying value of an interest-bearing hedged item made under an effective fair value hedge that is amortized upon discontinuation of the fair value hedge.

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Nominal or face amount used to calculate payments on the derivative asset.

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Description of the relevant terms of the derivative. Includes the type of instrument, risk being hedged, notional amount, counterparty, inception date, maturity date, relevant interest rates, strike price, cap price, and floor price.

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Fair value, before effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets elected not to be offset. Excludes assets not subject to a master netting arrangement.

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The estimated value of gains (losses), net anticipated to be transferred in the future from accumulated other comprehensive income into earnings.

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Maximum length of time over which 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.

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Derivative Financial Instruments - Additional Information (Detail) - USD ($)	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017	Dec. 31, 2017
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Derivative assets	$ 61,800,000		$ 61,800,000		$ 57,800,000
Fair Value Hedging
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Remaining cumulative basis adjustments on discontinued hedge relationship	(1,500,000)		$ (1,500,000)
Cash Flow Hedging
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Maximum length of future cash flow hedges			9 years 9 months 18 days
Accumulated net gain on derivative contracts included in accumulated other comprehensive loss expected to be recognized in the Consolidated Statements of Comprehensive Income in the following 12 months, net of tax			$ 13,500,000
Interest-Rate Contracts
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Notional amount of outstanding contracts	3,347,700,000		3,347,700,000
Notional maturities for interest-rate contracts 2018	340,800,000		340,800,000
Notional maturities for interest-rate contracts 2019	923,600,000		923,600,000
Notional maturities for interest-rate contracts 2020	429,900,000		429,900,000
Notional maturities for interest-rate contracts 2021	1,261,900,000		1,261,900,000
Notional maturities for interest-rate contracts 2022	268,200,000		268,200,000
Notional maturities for interest-rate contracts 2023	42,200,000		42,200,000
Notional maturities for interest-rate contracts thereafter	81,100,000		81,100,000
Reclassification from AOCI	(3,700,000)	$ 24,600,000	(86,500,000)	$ 110,400,000
Foreign-exchange contracts
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Derivative notional amount outstanding	806,300,000		$ 806,300,000
Foreign-exchange contracts maturity period			within one year
Reclassification from AOCI	3,200,000	3,500,000	$ 700,000	19,200,000
Foreign-exchange contracts \| Cash Flow Hedging \| Financial Services
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Reclassification from AOCI	0	$ 0	0	$ 0
Designated under hedge accounting
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Derivative assets	$ 61,000,000		$ 61,000,000		$ 57,100,000