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

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.

+ 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 (c)
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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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The aggregate fair value amounts of derivative instruments that contain credit-risk-related contingent features that are in a net liability position at the end of the reporting period. For nonderivative instruments that are designated and qualify as hedging instruments, the fair value amounts are the carrying value of the nonderivative hedging instrument, including the adjustment for the foreign currency transaction gain (loss) on that instrument.

+ References

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-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4H
-Subparagraph (c)
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- Definition

The number of derivative instruments of a particular group held by the entity.

+ References

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-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
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-SubTopic 10
-Section 50
-Paragraph 1B
-URI http://asc.fasb.org/extlink&oid=109980867&loc=SL5580258-113959

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- Definition

Number of interest rate derivative instruments held by the entity at the reporting date.

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Derivative Financial Instruments (Narrative) (Detail)	3 Months Ended
Derivative Financial Instruments (Narrative) (Detail)	Mar. 31, 2019 USD ($) derivative_instruments	Dec. 31, 2018 derivative_instruments	Mar. 31, 2018 derivative_instruments
Derivative Instruments, Gain (Loss) [Line Items]
Amount to be reclassified from accumulated other comprehensive income to interest expense in the next twelve months	$ 7,700,000
Net derivative liability position, aggregate fair value	36,500,000
Interest Rate Contract \| Not Designated as Hedging Instrument
Derivative Instruments, Gain (Loss) [Line Items]
Notional amount	6,400,000,000
Forward Commitments to Sell Mortgage Loans \| Not Designated as Hedging Instrument
Derivative Instruments, Gain (Loss) [Line Items]
Notional amount	651,900,000
Interest Rate Lock Commitments \| Not Designated as Hedging Instrument
Derivative Instruments, Gain (Loss) [Line Items]
Notional amount	403,200,000
Foreign Exchange Contract \| Not Designated as Hedging Instrument
Derivative Instruments, Gain (Loss) [Line Items]
Notional amount	$ 37,100,000
Covered Call Options \| Not Designated as Hedging Instrument
Derivative Instruments, Gain (Loss) [Line Items]
Number of derivative instruments held \| derivative_instruments	0	0	0
Cash Flow Hedging \| Cash flow hedge of variable rate deposits \| Interest Rate Swap \| Designated as Hedging Instrument
Derivative Instruments, Gain (Loss) [Line Items]
Number of interest rate derivatives held \| derivative_instruments	3
Cash Flow Hedging \| Cash flow hedge of variable rate deposits \| Interest Rate Collar \| Designated as Hedging Instrument
Derivative Instruments, Gain (Loss) [Line Items]
Number of derivative instruments held \| derivative_instruments	1
Fair Value Hedging \| Interest Rate Swap \| Designated as Hedging Instrument
Derivative Instruments, Gain (Loss) [Line Items]
Number of interest rate derivatives held \| derivative_instruments	16
Notional amount	$ 172,300,000.0
Fair Value Hedging \| Interest Rate Swap \| Effective after March 31, 2019 \| Designated as Hedging Instrument
Derivative Instruments, Gain (Loss) [Line Items]
Number of interest rate derivatives held \| derivative_instruments	1
Notional amount	$ 6,900,000.0