Regulatory Matters - Additional Information (Detail) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2016	Dec. 31, 2015
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
Potential maximum dividends without prior regulatory approval	$ 42,200
Average required reserve balance in Federal Reserve Bank	$ 2,000	$ 5,000
Percentage of Risk-weighted assets in bank holding companies in total capital	8.00%
Common equity tier 1, minimum value	4.50%
Common equity tier 1, well capitalized	6.50%
Percentage of Risk-weighted assets in banking subsidiaries	6.00%
Percentage of well-capitalized levels of Tier 1 risk-based capital	8.00%
Percentage of well-capitalized levels of total risk-based capital	10.00%
Percentage of well-capitalized levels of Tier 1 leverage capital	5.00%
Junior subordinated debt	$ 137,559
Provision of the Dodd-Frank	15,000,000
Trust Preferred Securities	$ 133,286
Minimum [Member]
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
Minimum Tier 1 leverage ratio	4.00%
WesBanco Bank Inc [Member]
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
Percentage of Risk-weighted assets in bank holding companies in total capital	8.00%
Common equity tier 1, minimum value	4.50%
Common equity tier 1, well capitalized	6.50%
Percentage of Risk-weighted assets in banking subsidiaries	6.00%
Percentage of well-capitalized levels of Tier 1 risk-based capital	8.00%
Percentage of well-capitalized levels of total risk-based capital	10.00%
Percentage of well-capitalized levels of Tier 1 leverage capital	5.00%
Junior Subordinated Debt [Member]
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
Junior subordinated debt	$ 137,600

The minimum Total risk based capital ratio (total capital divided by risk weighted assets) required for capital adequacy purposes under 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 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.

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The amount of excess Tier 1 Leverage Capital divided by average assets as defined in the regulations.

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Including the current and noncurrent portions, the carrying value of junior subordinated long-term debt owed to unconsolidated subsidiary trusts as of the balance sheet date. Such debt places a lender in a lien position behind debt having a higher priority of repayment in liquidation of the entity's assets and was initially scheduled to be repaid after one year or beyond the normal operating cycle if longer.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
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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 minimum Tier One Capital Ratio (Tier one capital divided by risk-weighted assets) required for capital adequacy purposes under the regulatory framework for prompt corrective action.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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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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Assets threshold provision of Dodd Frank Act.

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Average non interest bearing reserve balance required in federal reserve bank.

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Bank dividend restriction amount.

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Common equity tier one capital required for capital adequacy to average assets.

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Trust Preferred Securities Outstanding

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