Investment Securities (Amortized Cost, Unrealized Gains And Losses, And Fair Value Of Investment Securities) (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Investment Holdings [Line Items]
Available-for-sale securities, amortized cost	$ 3,864,355	$ 2,801,500
Available-for-sale securities, unrealized gains	58,106	131,850
Available-for-sale securities, unrealized losses	(52,026)	(792)
Available for sale, at fair value	3,870,435	2,932,558
Held to maturity, at amortized cost	2,744	3,034
Held-to-maturity securities, unrecognized gains	770	849
Held-to-maturity securities, unrecognized losses	0	0
Held-to-maturity securities, fair value	3,514	3,883
U.S. Treasury and agencies
Investment Holdings [Line Items]
Available-for-sale securities, amortized cost	894,969	698,243
Available-for-sale securities, unrealized gains	27,279	64,271
Available-for-sale securities, unrealized losses	(4,195)	(312)
Available for sale, at fair value	918,053	762,202
Obligations of states and political subdivisions
Investment Holdings [Line Items]
Available-for-sale securities, amortized cost	320,338	263,546
Available-for-sale securities, unrealized gains	11,734	15,996
Available-for-sale securities, unrealized losses	(1,288)	(31)
Available for sale, at fair value	330,784	279,511
Residential mortgage-backed securities and collateralized mortgage obligations
Investment Holdings [Line Items]
Available-for-sale securities, amortized cost	2,649,048	1,839,711
Available-for-sale securities, unrealized gains	19,093	51,583
Available-for-sale securities, unrealized losses	(46,543)	(449)
Available for sale, at fair value	2,621,598	1,890,845
Held to maturity, at amortized cost	2,744	3,034
Held-to-maturity securities, unrecognized gains	770	849
Held-to-maturity securities, unrecognized losses	0	0
Held-to-maturity securities, fair value	$ 3,514	$ 3,883

Amount, before tax, of unrealized gain in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Amount, before tax, of unrealized loss in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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