Deposits (Schedule of Detailed Deposits) (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Banking And Thrift Interest [Abstract]
Noninterest-bearing deposits	$ 14,392,808	$ 12,199,750
Interest-bearing retail transaction and savings deposits	11,677,333	10,435,362
Interest-bearing public fund deposits, Public fund transaction and savings deposits	3,216,651	3,068,555
Interest-bearing public fund deposits, Public fund time deposits	77,956	166,381
Total interest-bearing public fund deposits	3,294,607	3,234,936
Retail time deposits	1,091,959	1,813,705
Brokered time deposits	9,190	14,124
Total interest-bearing deposits	16,073,089	15,498,127
Total deposits	$ 30,465,897	$ 27,697,877