Consolidated Balance Sheets (Unaudited) (Parenthetical) - USD ($) $ in Thousands	Jun. 30, 2022	Dec. 31, 2021
Statement of Financial Position [Abstract]
Securities available for sale, amortized cost	$ 6,358,434	$ 6,984,530
Securities held to maturity, fair value	2,615,798	1,631,482
Loans held-for-sale, fair value	21,496	41,022
Property and equipment, accumulated depreciation	290,880	280,065
Right of use assets, accumulated amortization	$ 40,312	$ 34,425
Preferred stock, par value per share	$ 20.00	$ 20.00
Common stock, par value per share	$ 3.33	$ 3.33