BENEFIT PLANS - Defined Contribution Plans (Details) - USD ($) $ in Millions |
12 Months Ended | ||
|---|---|---|---|
Dec. 31, 2017 |
Dec. 31, 2016 |
Dec. 31, 2015 |
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| Retirement Benefits [Abstract] | |||
| Defined contribution plan | $ 35 | $ 36 | $ 32 |
| Shares in Huntington common stock (in shares) | 13,566 | 11,748 | |
| Market value of Huntington common stock | $ 198 | $ 162 | |
| Dividends received on shares of Huntington stock | $ 4 | $ 4 | |
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- Definition Defined Contribution Plan, Amount of Employer and Related Party Securities Included in Plan Assets No definition available.
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- Definition Defined Contribution Plan, Dividends Received on Employer and Related Party Securities Included in Plan Assets No definition available.
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- Definition Defined Contribution Plan, Number of Shares of Equity Securities Issued by Employer and Related Parties Included in Plan Assets No definition available.
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- References No definition available.
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- Definition Amount of cost for defined contribution plan. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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