Quarterly report pursuant to Section 13 or 15(d)

LONG-TERM DEBT (Details)

v3.5.0.2
LONG-TERM DEBT (Details) - USD ($)
Aug. 16, 2016
Aug. 09, 2016
Mar. 14, 2016
Senior Notes | 3.15% Senior notes Due March 2021      
Debt Instrument [Line Items]      
Debt face amount     $ 1,000,000,000.0
Debt percent of value     99.803%
Debt stated interest rate     3.15%
Debt issuance costs     $ 5,000,000
Senior Notes | 2.3% Senior Notes Due January 2022      
Debt Instrument [Line Items]      
Debt face amount   $ 1,000,000,000.0  
Debt percent of value   99.849%  
Debt stated interest rate   2.30%  
Debt issuance costs   $ 6,000,000  
FirstMerit Bank      
Debt Instrument [Line Items]      
Long-term debt assumed $ 519,971,000    
FirstMerit Bank | Subordinated debt      
Debt Instrument [Line Items]      
Long-term debt assumed $ 520,000,000