FAIR VALUE MEASUREMENTS (Schedule of Financial Assets and Liabilities Measured at Fair Value on Recurring Basis) (Details) - USD ($) $ in Thousands	Sep. 30, 2023	Dec. 31, 2022
ASSETS
Securities available for sale, at fair value	$ 2,084,928	$ 2,741,816
Loans held for sale	6,608	3,936
Financial Derivatives	123,019	80,310
LIABILITIES
Financial Derivatives	291,769	236,000
Quoted Prices in Active Markets for Identical Assets Level 1
ASSETS
Securities available for sale, at fair value	59,568	56,606
Loans held for sale	0	0
Financial Derivatives	0	0
LIABILITIES
Financial Derivatives	0	0
Significant Other Observable Inputs Level 2
ASSETS
Securities available for sale, at fair value	2,025,360	2,685,210
Loans held for sale	6,608	3,936
Financial Derivatives	123,019	80,310
LIABILITIES
Financial Derivatives	291,769	236,000
Significant Unobservable Inputs Level 3
ASSETS
Securities available for sale, at fair value	0	0
Loans held for sale	0	0
Financial Derivatives	0	0
LIABILITIES
Financial Derivatives	0	0
Recurring
ASSETS
Loans held for sale	6,608	3,936
Financial Derivatives	123,019	80,310
LIABILITIES
Financial Derivatives	291,769	236,000
Recurring | Quoted Prices in Active Markets for Identical Assets Level 1
ASSETS
Loans held for sale	0	0
Financial Derivatives	0	0
LIABILITIES
Financial Derivatives	0	0
Recurring | Significant Other Observable Inputs Level 2
ASSETS
Loans held for sale	6,608	3,936
Financial Derivatives	123,019	80,310
LIABILITIES
Financial Derivatives	291,769	236,000
Recurring | Significant Unobservable Inputs Level 3
ASSETS
Loans held for sale	0	0
Financial Derivatives	0	0
LIABILITIES
Financial Derivatives	0	0
U.S. government and agency securities
ASSETS
Securities available for sale, at fair value	61,838	61,943
U.S. government and agency securities | Recurring
ASSETS
Securities available for sale, at fair value	61,838	61,943
U.S. government and agency securities | Recurring | Quoted Prices in Active Markets for Identical Assets Level 1
ASSETS
Securities available for sale, at fair value	59,568	56,606
U.S. government and agency securities | Recurring | Significant Other Observable Inputs Level 2
ASSETS
Securities available for sale, at fair value	2,270	5,337
U.S. government and agency securities | Recurring | Significant Unobservable Inputs Level 3
ASSETS
Securities available for sale, at fair value	0	0
Obligations of states and political subdivisions
ASSETS
Securities available for sale, at fair value	417,460	807,435
Obligations of states and political subdivisions | Recurring
ASSETS
Securities available for sale, at fair value	417,460	807,435
Obligations of states and political subdivisions | Recurring | Quoted Prices in Active Markets for Identical Assets Level 1
ASSETS
Securities available for sale, at fair value	0	0
Obligations of states and political subdivisions | Recurring | Significant Other Observable Inputs Level 2
ASSETS
Securities available for sale, at fair value	417,460	807,435
Obligations of states and political subdivisions | Recurring | Significant Unobservable Inputs Level 3
ASSETS
Securities available for sale, at fair value	0	0
Corporate and other bonds
ASSETS
Securities available for sale, at fair value	242,818	226,380
Corporate and other bonds | Recurring
ASSETS
Securities available for sale, at fair value	242,818	226,380
Corporate and other bonds | Recurring | Quoted Prices in Active Markets for Identical Assets Level 1
ASSETS
Securities available for sale, at fair value	0	0
Corporate and other bonds | Recurring | Significant Other Observable Inputs Level 2
ASSETS
Securities available for sale, at fair value	242,818	226,380
Corporate and other bonds | Recurring | Significant Unobservable Inputs Level 3
ASSETS
Securities available for sale, at fair value	0	0
Mortgage-backed securities | Recurring
ASSETS
Securities available for sale, at fair value	1,361,085	1,644,394
Mortgage-backed securities | Recurring | Quoted Prices in Active Markets for Identical Assets Level 1
ASSETS
Securities available for sale, at fair value	0	0
Mortgage-backed securities | Recurring | Significant Other Observable Inputs Level 2
ASSETS
Securities available for sale, at fair value	1,361,085	1,644,394
Mortgage-backed securities | Recurring | Significant Unobservable Inputs Level 3
ASSETS
Securities available for sale, at fair value	0	0
Other securities
ASSETS
Securities available for sale, at fair value	1,727	1,664
Other securities | Recurring
ASSETS
Securities available for sale, at fair value	1,727	1,664
Other securities | Recurring | Quoted Prices in Active Markets for Identical Assets Level 1
ASSETS
Securities available for sale, at fair value	0	0
Other securities | Recurring | Significant Other Observable Inputs Level 2
ASSETS
Securities available for sale, at fair value	1,727	1,664
Other securities | Recurring | Significant Unobservable Inputs Level 3
ASSETS
Securities available for sale, at fair value	$ 0	$ 0