XML 136 R123.htm IDEA: XBRL DOCUMENT
v3.22.4

Fair Value of Assets and Liabilities (Schedule of Valuation Techniques and Significant Unobservable Inputs Used to Measure Both Recurring and Nonrecurring) (Details) | Dec. 31, 2022 USD ($) $ / shares year | Dec. 31, 2021 USD ($) | Dec. 31, 2020 USD ($) | Dec. 31, 2019 USD ($)
--- | --- | --- | --- | ---
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |  |
Available-for-sale securities | $ 3,243,017,000 | $ 2,327,793,000 |  |
Loans held-for-investment | 179,932,000 | 38,598,000 |  |
MSRs | 230,225,000 | 147,571,000 | $ 92,081,000 | $ 85,638,000
Individually assessed loans - foreclosure probable and collateral-dependent | 90,197,000 | 93,270,000 |  |
Municipal securities |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |  |
Available-for-sale securities | 168,655,000 | 165,594,000 |  |
Level 3 |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |  |
Individually assessed loans - foreclosure probable and collateral-dependent | 90,200,000 |  |  |
Measured at fair value on a recurring basis: |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |  |
Mortgage loans held-for-sale | 299,935,000 | 817,912,000 |  |
Loans held-for-investment | 179,932,000 | 38,598,000 |  |
MSRs | 230,225,000 | 147,571,000 |  |
Measured at fair value on a recurring basis: | Municipal securities |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |  |
Available-for-sale securities | 168,655,000 | 165,594,000 |  |
Measured at fair value on a recurring basis: | Level 3 |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |  |
Mortgage loans held-for-sale | 48,655,000 | 0 |  |
Loans held-for-investment | 84,165,000 | 15,891,000 |  |
MSRs | 230,225,000 | 147,571,000 |  |
Measured at fair value on a recurring basis: | Level 3 | Municipal securities |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |  |
Available-for-sale securities | $ 117,537,000 | $ 105,687,000 |  |
Measured at fair value on a recurring basis: | Discount rate | Level 3 | Discounted cash flows |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |  |
Loans Held-for-sale, Measurement Input | 0.0621 |  |  |
Measured at fair value on a recurring basis: | Discount rate | Level 3 | Discounted cash flows | Minimum |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |  |
Loans held-for-investment, measurement input | 0.0621 |  |  |
MSRs, measurement input | 0.07 |  |  |
Measured at fair value on a recurring basis: | Discount rate | Level 3 | Discounted cash flows | Maximum |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |  |
Loans held-for-investment, measurement input | 0.0675 |  |  |
MSRs, measurement input | 0.24 |  |  |
Measured at fair value on a recurring basis: | Discount rate | Level 3 | Discounted cash flows | Weighted Average |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |  |
Loans held-for-investment, measurement input | 0.0626 |  |  |
MSRs, measurement input | 0.1030 |  |  |
Loans Held-for-sale, Measurement Input | 0.0621 |  |  |
Measured at fair value on a recurring basis: | Credit discount | Level 3 | Discounted cash flows | Minimum |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |  |
Loans held-for-investment, measurement input | 0 |  |  |
Loans Held-for-sale, Measurement Input | 0 |  |  |
Measured at fair value on a recurring basis: | Credit discount | Level 3 | Discounted cash flows | Maximum |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |  |
Loans held-for-investment, measurement input | 0.12 |  |  |
Loans Held-for-sale, Measurement Input | 0.12 |  |  |
Measured at fair value on a recurring basis: | Credit discount | Level 3 | Discounted cash flows | Weighted Average |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |  |
Loans held-for-investment, measurement input | 0.0077 |  |  |
Loans Held-for-sale, Measurement Input | 0.0033 |  |  |
Measured at fair value on a recurring basis: | Constant prepayment rate (CPR) - current loans | Level 3 | Discounted cash flows |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |  |
Loans held-for-investment, measurement input | 0.0662 |  |  |
Measured at fair value on a recurring basis: | Constant prepayment rate (CPR) - current loans | Level 3 | Discounted cash flows | Minimum |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |  |
MSRs, measurement input | 0 |  |  |
Measured at fair value on a recurring basis: | Constant prepayment rate (CPR) - current loans | Level 3 | Discounted cash flows | Maximum |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |  |
MSRs, measurement input | 1 |  |  |
Measured at fair value on a recurring basis: | Constant prepayment rate (CPR) - current loans | Level 3 | Discounted cash flows | Weighted Average |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |  |
Loans held-for-investment, measurement input | 0.0662 |  |  |
MSRs, measurement input | 0.0662 |  |  |
Measured at fair value on a recurring basis: | Average life - delinquent loans (in years) | Level 3 | Discounted cash flows | Minimum |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |  |
Loans held-for-investment, measurement input | year | 1.4 |  |  |
Measured at fair value on a recurring basis: | Average life - delinquent loans (in years) | Level 3 | Discounted cash flows | Maximum |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |  |
Loans held-for-investment, measurement input | year | 10 |  |  |
Measured at fair value on a recurring basis: | Average life - delinquent loans (in years) | Level 3 | Discounted cash flows | Weighted Average |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |  |
Loans held-for-investment, measurement input | year | 5.8 |  |  |
Measured at fair value on a recurring basis: | Cost of servicing | Level 3 | Discounted cash flows | Minimum |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |  |
MSRs, measurement input | $ / shares | 70 |  |  |
Measured at fair value on a recurring basis: | Cost of servicing | Level 3 | Discounted cash flows | Maximum |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |  |
MSRs, measurement input | $ / shares | 200 |  |  |
Measured at fair value on a recurring basis: | Cost of servicing | Level 3 | Discounted cash flows | Weighted Average |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |  |
MSRs, measurement input | 75 |  |  |
Measured at fair value on a recurring basis: | Cost of servicing - delinquent | Level 3 | Discounted cash flows | Minimum |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |  |
MSRs, measurement input | $ / shares | 200 |  |  |
Measured at fair value on a recurring basis: | Cost of servicing - delinquent | Level 3 | Discounted cash flows | Maximum |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |  |
MSRs, measurement input | $ / shares | 1,000 |  |  |
Measured at fair value on a recurring basis: | Cost of servicing - delinquent | Level 3 | Discounted cash flows | Weighted Average |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |  |
MSRs, measurement input | 343 |  |  |
Measured at fair value on a recurring basis: | Pull-through rate | Level 3 | Discounted cash flows | Minimum |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |  |
Derivatives, measurement input | 0.35 |  |  |
Measured at fair value on a recurring basis: | Pull-through rate | Level 3 | Discounted cash flows | Maximum |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |  |
Derivatives, measurement input | 1 |  |  |
Measured at fair value on a recurring basis: | Pull-through rate | Level 3 | Discounted cash flows | Weighted Average |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |  |
Derivatives, measurement input | 0.8612 |  |  |
Measured at fair value on a non-recurring basis: |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |  |
Individually assessed loans - foreclosure probable and collateral-dependent | $ 69,019,000 |  |  |
Other real estate owned | 9,900,000 |  |  |
Measured at fair value on a non-recurring basis: | Level 3 |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |  |
Individually assessed loans - foreclosure probable and collateral-dependent | 69,019,000 |  |  |
Other real estate owned | $ 9,900,000 |  |  |
Measured at fair value on a non-recurring basis: | Appraisal adjustment - cost of sale | Level 3 | Appraisal value |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |  |
Impaired loans - collateral based, measurement input | 0.10 |  |  |
Other real estate owned, measurement input | 0.10 |  |  |
Measured at fair value on a non-recurring basis: | Appraisal adjustment - cost of sale | Level 3 | Appraisal value | Weighted Average |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |  |
Impaired loans - collateral based, measurement input | 0.1000 |  |  |
Other real estate owned, measurement input | 0.1000 |  |  |

X
- Definition Amount excluding accrued interest, of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale). + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 30 -Section 45 -Paragraph 1 -URI https://asc.fasb.org/extlink&oid=124258926&loc=SL82898722-210454 + Details
Name: | us-gaap_DebtSecuritiesAvailableForSaleExcludingAccruedInterest
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Value of input used to measure derivative asset. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (bbb)(2) -URI https://asc.fasb.org/extlink&oid=126976982&loc=d3e19207-110258 + Details
Name: | us-gaap_DerivativeAssetMeasurementInput
Namespace Prefix: | us-gaap_
Data Type: | xbrli:decimalItemType
Balance Type: | na
Period Type: | instant

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_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisValuationTechniquesLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition The balance of financing receivables that were individually evaluated for impairment. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 11B -Subparagraph (h) -URI https://asc.fasb.org/extlink&oid=123577603&loc=SL6953423-111524 + Details
Name: | us-gaap_FinancingReceivableIndividuallyEvaluatedForImpairment
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Fair value portion of loans held-for-sale including, but not limited to, mortgage loans and finance receivables. + References No definition available. + Details
Name: | us-gaap_LoansHeldForSaleFairValueDisclosure
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Value of input used to measure loan, held for sale. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (bbb)(2) -URI https://asc.fasb.org/extlink&oid=126976982&loc=d3e19207-110258 + Details
Name: | us-gaap_LoansHeldForSaleMeasurementInput
Namespace Prefix: | us-gaap_
Data Type: | xbrli:decimalItemType
Balance Type: | na
Period Type: | instant

X
- Definition Carrying amount as of the balance sheet date of other real estate and foreclosed assets. Other real estate may include real estate investments, real estate loans that qualify as investments in real estate, and premises that are no longer used in operations may also be included in real estate owned. Foreclosed assets include all assets obtained in full or partial satisfaction of a debt arrangement through foreclosure proceedings. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03.10(4)) -URI https://asc.fasb.org/extlink&oid=126897435&loc=d3e534808-122878 + Details
Name: | us-gaap_OtherRealEstateAndForeclosedAssets
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Value of input used to measure real estate owned by financial institution by financial institution which is not directly related to its business. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (bbb)(2) -URI https://asc.fasb.org/extlink&oid=126976982&loc=d3e19207-110258 + Details
Name: | us-gaap_OtherRealEstateOwnedMeasurementInput
Namespace Prefix: | us-gaap_
Data Type: | xbrli:decimalItemType
Balance Type: | na
Period Type: | instant

X
- Definition Fair value of an asset representing net future revenue from contractually specified servicing fees, late charges, and other ancillary revenues, in excess of future costs related to servicing arrangements. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 860 -SubTopic 50 -Section 45 -Paragraph 2 -Subparagraph (b) -URI https://asc.fasb.org/extlink&oid=6469459&loc=d3e122501-111745 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 860 -SubTopic 50 -Section 45 -Paragraph 1 -URI https://asc.fasb.org/extlink&oid=6469459&loc=d3e122492-111745 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 860 -SubTopic 50 -Section 50 -Paragraph 3 -Subparagraph (a)(1) -URI https://asc.fasb.org/extlink&oid=128311188&loc=d3e122625-111746 Reference 4: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 860 -SubTopic 50 -Section 45 -Paragraph 2 -Subparagraph (a) -URI https://asc.fasb.org/extlink&oid=6469459&loc=d3e122501-111745 + Details
Name: | us-gaap_ServicingAssetAtFairValueAmount
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Value of input used to measure servicing asset. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (bbb)(2) -URI https://asc.fasb.org/extlink&oid=126976982&loc=d3e19207-110258 + Details
Name: | us-gaap_ServicingAssetMeasurementInput
Namespace Prefix: | us-gaap_
Data Type: | xbrli:decimalItemType
Balance Type: | na
Period Type: | instant

X
- Definition Impaired Financing Receivable, Measurement Input + References No definition available. + Details
Name: | wtfc_ImpairedFinancingReceivableMeasurementInput
Namespace Prefix: | wtfc_
Data Type: | xbrli:pureItemType
Balance Type: | na
Period Type: | instant

X
- Definition Loans Held-For-Investment, Fair Value Disclosure + References No definition available. + Details
Name: | wtfc_LoansHeldForInvestmentFairValueDisclosure
Namespace Prefix: | wtfc_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Loans Held-For-Investment, Measurement Input + References No definition available. + Details
Name: | wtfc_LoansHeldForInvestmentMeasurementInput
Namespace Prefix: | wtfc_
Data Type: | xbrli:decimalItemType
Balance Type: | na
Period Type: | instant

X
- Details
Name: | us-gaap_FinancialInstrumentAxis=us-gaap_MunicipalBondsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FairValueByFairValueHierarchyLevelAxis=us-gaap_FairValueInputsLevel3Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FairValueByMeasurementFrequencyAxis=us-gaap_FairValueMeasurementsRecurringMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_MeasurementInputTypeAxis=us-gaap_MeasurementInputDiscountRateMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_ValuationTechniqueAxis=us-gaap_ValuationTechniqueDiscountedCashFlowMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_RangeAxis=srt_MinimumMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_RangeAxis=srt_MaximumMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_RangeAxis=srt_WeightedAverageMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_MeasurementInputTypeAxis=us-gaap_MeasurementInputEntityCreditRiskMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_MeasurementInputTypeAxis=us-gaap_MeasurementInputConstantPrepaymentRateMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_MeasurementInputTypeAxis=us-gaap_MeasurementInputExpectedTermMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_MeasurementInputTypeAxis=wtfc_MeasurementInputCostOfServicingMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_MeasurementInputTypeAxis=wtfc_MeasurementInputCostOfServicingDelinquentMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_MeasurementInputTypeAxis=wtfc_MeasurementInputPullThroughRateMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FairValueByMeasurementFrequencyAxis=us-gaap_FairValueMeasurementsNonrecurringMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_MeasurementInputTypeAxis=us-gaap_MeasurementInputDiscountForLackOfMarketabilityMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_ValuationTechniqueAxis=us-gaap_CostApproachValuationTechniqueMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |