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Investment Securities (Schedule of Investment Securities Portfolio Continuous Unrealized Loss Position) (Detail) $ in Thousands | Mar. 31, 2022 USD ($)
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Available-for-sale securities |
Continuous unrealized losses existing for less than 12 months, fair value | $ 2,296,022
Continuous unrealized losses existing for less than 12 months, unrealized losses | (128,973)
Continuous unrealized losses existing for greater than 12 months, fair value | 543,886
Continuous unrealized losses existing for greater than 12 months, unrealized losses | (67,848)
Total, fair value | 2,839,908
Total, unrealized losses | (196,821)
U.S. Treasury |
Available-for-sale securities |
Continuous unrealized losses existing for less than 12 months, fair value | 0
Continuous unrealized losses existing for less than 12 months, unrealized losses | 0
Continuous unrealized losses existing for greater than 12 months, fair value | 0
Continuous unrealized losses existing for greater than 12 months, unrealized losses | 0
Total, fair value | 0
Total, unrealized losses | 0
U.S. Government agencies |
Available-for-sale securities |
Continuous unrealized losses existing for less than 12 months, fair value | 9,271
Continuous unrealized losses existing for less than 12 months, unrealized losses | (729)
Continuous unrealized losses existing for greater than 12 months, fair value | 0
Continuous unrealized losses existing for greater than 12 months, unrealized losses | 0
Total, fair value | 9,271
Total, unrealized losses | (729)
Municipal |
Available-for-sale securities |
Continuous unrealized losses existing for less than 12 months, fair value | 92,896
Continuous unrealized losses existing for less than 12 months, unrealized losses | (2,861)
Continuous unrealized losses existing for greater than 12 months, fair value | 3,553
Continuous unrealized losses existing for greater than 12 months, unrealized losses | (232)
Total, fair value | 96,449
Total, unrealized losses | (3,093)
Financial issuers |
Available-for-sale securities |
Continuous unrealized losses existing for less than 12 months, fair value | 20,814
Continuous unrealized losses existing for less than 12 months, unrealized losses | (1,186)
Continuous unrealized losses existing for greater than 12 months, fair value | 58,133
Continuous unrealized losses existing for greater than 12 months, unrealized losses | (3,861)
Total, fair value | 78,947
Total, unrealized losses | (5,047)
Other |
Available-for-sale securities |
Continuous unrealized losses existing for less than 12 months, fair value | 991
Continuous unrealized losses existing for less than 12 months, unrealized losses | (9)
Continuous unrealized losses existing for greater than 12 months, fair value | 0
Continuous unrealized losses existing for greater than 12 months, unrealized losses | 0
Total, fair value | 991
Total, unrealized losses | (9)
Mortgage-backed securities |
Available-for-sale securities |
Continuous unrealized losses existing for less than 12 months, fair value | 2,078,794
Continuous unrealized losses existing for less than 12 months, unrealized losses | (114,144)
Continuous unrealized losses existing for greater than 12 months, fair value | 482,200
Continuous unrealized losses existing for greater than 12 months, unrealized losses | (63,755)
Total, fair value | 2,560,994
Total, unrealized losses | (177,899)
Collateralized mortgage obligations |
Available-for-sale securities |
Continuous unrealized losses existing for less than 12 months, fair value | 93,256
Continuous unrealized losses existing for less than 12 months, unrealized losses | (10,044)
Continuous unrealized losses existing for greater than 12 months, fair value | 0
Continuous unrealized losses existing for greater than 12 months, unrealized losses | 0
Total, fair value | 93,256
Total, unrealized losses | $ (10,044)

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