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Bank segment - Components of Investment Securities (Details) $ in Thousands | Jun. 30, 2024 USD ($) issue | Dec. 31, 2023 USD ($) issue
--- | --- | ---
Available-for-sale |  |
Amortized cost | $ 1,288,002 |
Available-for-sale investment securities, at fair value | 1,061,687 | $ 1,136,439
Held-to-maturity |  |
Held-to-maturity investment securities, at amortized cost | 1,179,182 | 1,201,314
Held-to-maturity investment securities | 1,058,691 |
American Savings Bank (ASB) |  |
Available-for-sale |  |
Amortized cost | 1,288,002 | 1,341,886
Gross unrealized gains | 3 | 0
Gross unrealized losses | (226,318) | (205,447)
Available-for-sale investment securities, at fair value | $ 1,061,687 | $ 1,136,439
Gross unrealized losses, less than 12 months, number of issues | issue | 0 | 3
Gross unrealized losses, less than 12 months, fair value | $ 0 | $ 1,649
Gross unrealized losses, less than 12 months, amount | $ 0 | $ (22)
Gross unrealized losses, 12 months or longer, number of issues | issue | 126 | 128
Gross unrealized losses, 12 months or longer, fair value | $ 1,047,001 | $ 1,120,432
Gross unrealized losses, 12 months or more, amount | (226,318) | (205,425)
Held-to-maturity |  |
Held-to-maturity investment securities, at amortized cost | 1,179,182 | 1,201,314
Gross unrealized gains | 41 | 2,221
Gross unrealized losses | (120,532) | (99,867)
Held-to-maturity investment securities | $ 1,058,691 | $ 1,103,668
Less than 12 months, number of issues | issue | 30 | 37
Less than 12 months, fair value | $ 314,047 | $ 378,326
Less than 12 months, amount | $ (9,253) | $ (7,610)
12 months or longer, number of issues | issue | 75 | 46
12 months or longer: fair value | $ 737,702 | $ 484,864
12 months or longer, amount | (111,279) | (92,257)
U.S. Treasury and federal agency obligations | American Savings Bank (ASB) |  |
Available-for-sale |  |
Amortized cost | 9,226 | 12,437
Gross unrealized gains | 0 | 0
Gross unrealized losses | (343) | (427)
Available-for-sale investment securities, at fair value | $ 8,883 | $ 12,010
Gross unrealized losses, less than 12 months, number of issues | issue | 0 | 0
Gross unrealized losses, less than 12 months, fair value | $ 0 | $ 0
Gross unrealized losses, less than 12 months, amount | $ 0 | $ 0
Gross unrealized losses, 12 months or longer, number of issues | issue | 8 | 9
Gross unrealized losses, 12 months or longer, fair value | $ 8,883 | $ 12,010
Gross unrealized losses, 12 months or more, amount | (343) | (427)
Held-to-maturity |  |
Held-to-maturity investment securities, at amortized cost | 59,929 | 59,917
Gross unrealized gains | 0 | 0
Gross unrealized losses | (7,839) | (7,135)
Held-to-maturity investment securities | $ 52,090 | $ 52,782
Less than 12 months, number of issues | issue | 0 | 0
Less than 12 months, fair value | $ 0 | $ 0
Less than 12 months, amount | $ 0 | $ 0
12 months or longer, number of issues | issue | 3 | 3
12 months or longer: fair value | $ 52,090 | $ 52,782
12 months or longer, amount | (7,839) | (7,135)
Mortgage-backed securities | American Savings Bank (ASB) |  |
Available-for-sale |  |
Amortized cost | 1,229,529 | 1,279,852
Gross unrealized gains | 3 | 0
Gross unrealized losses | (223,731) | (202,684)
Available-for-sale investment securities, at fair value | $ 1,005,801 | $ 1,077,168
Gross unrealized losses, less than 12 months, number of issues | issue | 0 | 3
Gross unrealized losses, less than 12 months, fair value | $ 0 | $ 1,649
Gross unrealized losses, less than 12 months, amount | $ 0 | $ (22)
Gross unrealized losses, 12 months or longer, number of issues | issue | 115 | 116
Gross unrealized losses, 12 months or longer, fair value | $ 1,005,191 | $ 1,075,519
Gross unrealized losses, 12 months or more, amount | (223,731) | (202,662)
Held-to-maturity |  |
Held-to-maturity investment securities, at amortized cost | 1,119,253 | 1,141,397
Gross unrealized gains | 41 | 2,221
Gross unrealized losses | (112,693) | (92,732)
Held-to-maturity investment securities | $ 1,006,601 | $ 1,050,886
Less than 12 months, number of issues | issue | 30 | 37
Less than 12 months, fair value | $ 314,047 | $ 378,326
Less than 12 months, amount | $ (9,253) | $ (7,610)
12 months or longer, number of issues | issue | 72 | 43
12 months or longer: fair value | $ 685,612 | $ 432,082
12 months or longer, amount | (103,440) | (85,122)
Corporate bonds | American Savings Bank (ASB) |  |
Available-for-sale |  |
Amortized cost | 35,171 | 35,239
Gross unrealized gains | 0 | 0
Gross unrealized losses | (2,244) | (2,336)
Available-for-sale investment securities, at fair value | $ 32,927 | $ 32,903
Gross unrealized losses, less than 12 months, number of issues | issue | 0 | 0
Gross unrealized losses, less than 12 months, fair value | $ 0 | $ 0
Gross unrealized losses, less than 12 months, amount | $ 0 | $ 0
Gross unrealized losses, 12 months or longer, number of issues | issue | 3 | 3
Gross unrealized losses, 12 months or longer, fair value | $ 32,927 | $ 32,903
Gross unrealized losses, 12 months or more, amount | (2,244) | (2,336)
Mortgage revenue bonds | American Savings Bank (ASB) |  |
Available-for-sale |  |
Amortized cost | 14,076 | 14,358
Gross unrealized gains | 0 | 0
Gross unrealized losses | 0 | 0
Available-for-sale investment securities, at fair value | $ 14,076 | $ 14,358
Gross unrealized losses, less than 12 months, number of issues | issue | 0 | 0
Gross unrealized losses, less than 12 months, fair value | $ 0 | $ 0
Gross unrealized losses, less than 12 months, amount | $ 0 | $ 0
Gross unrealized losses, 12 months or longer, number of issues | issue | 0 | 0
Gross unrealized losses, 12 months or longer, fair value | $ 0 | $ 0
Gross unrealized losses, 12 months or more, amount | $ 0 | $ 0

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