XML 89 R80.htm IDEA: XBRL DOCUMENT
v3.22.1

Derivative Financial Instruments (Derivatives in Fair Value Hedging Relationships) (Detail) - Designated as Hedging Instrument - Interest Rate Swap $ in Thousands | 3 Months Ended
--- | ---
Mar. 31, 2022 USD ($)
Interest and fees on loans |
Derivative [Line Items] |
Location of (Loss)/Gain Recognized in Income on Derivative | $ 16
Interest income - investment securities |
Derivative [Line Items] |
Location of (Loss)/Gain Recognized in Income on Derivative | 0
Loans, net of unearned income |
Derivative [Line Items] |
Carrying Amount of the Hedged Assets/(Liabilities) | 131,138
Cumulative Amount of Fair Value Hedging Adjustment Included in the Carrying Amount of the Hedged Assets/(Liabilities) | (5,664)
Cumulative Amount of Fair Value Hedging Adjustment Remaining for any Hedged Assets/(Liabilities) for which Hedge Accounting has been Discontinued | (125)
Available-for-sale debt securities |
Derivative [Line Items] |
Carrying Amount of the Hedged Assets/(Liabilities) | 1,070
Cumulative Amount of Fair Value Hedging Adjustment Included in the Carrying Amount of the Hedged Assets/(Liabilities) | 24
Cumulative Amount of Fair Value Hedging Adjustment Remaining for any Hedged Assets/(Liabilities) for which Hedge Accounting has been Discontinued | $ 0

X
- 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. + Details
Name: | us-gaap_DerivativeLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Total amount of gain (loss) derived from fair value hedges recognized in earnings in the 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 4C -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=125515794&loc=SL5624171-113959 + Details
Name: | us-gaap_GainLossOnFairValueHedgesRecognizedInEarnings
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Amount of cumulative increase (decrease) in fair value of hedged asset in fair value hedge, attributable to hedged risk, remaining after discontinued hedge. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4EE -Subparagraph (d) -URI http://asc.fasb.org/extlink&oid=125515794&loc=SL109999712-113959 + Details
Name: | us-gaap_HedgedAssetDiscontinuedFairValueHedgeCumulativeIncreaseDecrease
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Amount of asset hedged in fair value hedging relationship. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4EE -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=125515794&loc=SL109999712-113959 + Details
Name: | us-gaap_HedgedAssetFairValueHedge
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Amount of cumulative increase (decrease) in fair value of hedged asset in fair value hedge, attributable to hedged risk. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4EE -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=125515794&loc=SL109999712-113959 + Details
Name: | us-gaap_HedgedAssetFairValueHedgeCumulativeIncreaseDecrease
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Details
Name: | us-gaap_HedgingDesignationAxis=us-gaap_DesignatedAsHedgingInstrumentMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_IncomeStatementLocationAxis=wtfc_InterestandFeeIncomeLoansandLeasesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DerivativeInstrumentRiskAxis=us-gaap_InterestRateSwapMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_IncomeStatementLocationAxis=wtfc_InterestandDividendIncomeSecuritiesOperatingMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_BalanceSheetLocationAxis=us-gaap_LoansReceivableMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_BalanceSheetLocationAxis=us-gaap_AvailableforsaleSecuritiesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |