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The Total risk based capital ratio (total capital divided by risk weighted assets) required to be categorized as "well capitalized", in the regulatory framework for prompt corrective action.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 505
-Section 50
-Paragraph 1
-Subparagraph (c)(1)
-URI http://asc.fasb.org/extlink&oid=35709795&loc=SL5958568-112826

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The amount of Tier 1 Leverage Capital required to be categorized as well capitalized divided by average assets as defined in the regulatory framework for prompt corrective action.

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The Tier 1 capital ratio (Tier 1 capital divided by risk weighted assets) required to be categorized as "well capitalized" under the regulatory framework for prompt corrective action.

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Capital Infusion

No definition available.

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Common Equity Tier One Risk Based Capital To Risk Weighted Assets

No definition available.

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Number Of Banks Impacted By Regulations

No definition available.

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Number Of Banks Infused

No definition available.

Name:	wtfc_NumberOfBanksInfused
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Name:	dei_LegalEntityAxis=wtfc_BeverlyBankMember
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Name:	dei_LegalEntityAxis=wtfc_SchaumburgBankMember
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Name:	dei_LegalEntityAxis=wtfc_BarringtonBankMember
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