CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021
Statement of Comprehensive Income [Abstract]
NET INCOME	$ 47,965	$ 54,382	$ 91,928	$ 101,237
OTHER COMPREHENSIVE (LOSS) INCOME, NET OF INCOME TAXES:
Unrealized holding (loss) gain on securities—available-for-sale arising during the period	(129,352)	33,619	(282,416)	(39,488)
Income tax benefit (expense) related to securities—available-for-sale unrealized holding (losses)/gains	31,044	(8,069)	67,780	9,477
Reclassification for net gain on securities—available-for-sale realized in earnings	(32)	(77)	(467)	(516)
Income tax expense related to securities—available-for-sale realized gains	8	19	112	124
Unrealized gain (loss) on securities transferred from available-for-sale to held-to-maturity	904	0	(33,368)	0
Income tax (expense) benefit related to securities transferred from available-for-sale to held-to-maturity	(218)	0	8,008	0
Net unrealized loss on interest rate swaps used in cash flow hedges	(3,779)	0	(18,554)	0
Income tax benefit related to interest rate swaps used in cash flow hedges	907	0	4,453	0
Changes in fair value of junior subordinated debentures related to instrument specific credit risk	(1,719)	(272)	(2,932)	(546)
Income tax benefit related to junior subordinated debentures	413	65	704	131
Reclassification of fair value of junior subordinated debentures redeemed	0	0	765	0
Income tax expense related to junior subordinated debentures redeemed	0	0	(184)	0
Other comprehensive (loss) income	(101,824)	25,285	(256,099)	(30,818)
COMPREHENSIVE (LOSS) INCOME	$ (53,859)	$ 79,667	$ (164,171)	$ 70,419