SECURITIES - Unrealized Loss Position (Details) $ in Thousands	Jun. 30, 2026 USD ($) security	Dec. 31, 2025 USD ($) security
Debt Securities, Available-for-Sale, Unrealized Loss Position [Abstract]
Gross unrealized losses	$ (1,290,628)	$ (877,450)
Agency Mortgage-Backed Securities
Debt Securities, Available-for-Sale, Unrealized Loss Position, Accumulated Loss [Abstract]
Less than 12 months	29,060	2,942
12 Months or more	5,873,226	6,307,396
Estimated fair value	5,902,286	6,310,338
Debt Securities, Available-for-Sale, Unrealized Loss Position [Abstract]
Less than 12 months	(444)	(168)
12 Months or more	(560,498)	(494,102)
Gross unrealized losses	$ (560,942)	$ (494,270)
Debt Securities, Available-for-Sale, Continuous Unrealized Loss Position, Number of Positions [Abstract]
Less than 12 months \| security	16	1
12 Months or more \| security	1,266	1,268
Number of securities \| security	1,282	1,269

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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-Topic 320
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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), in continuous unrealized loss position for more than 12 months, without allowance for credit loss. Includes beneficial interest in securitized financial asset.

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Amount of accumulated unrealized loss on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in continuous unrealized loss position for 12 months or longer, without allowance for credit loss. Includes beneficial interest in securitized financial asset.

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Number of investments in debt securities measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in continuous unrealized loss position for 12 months or longer, without an allowance for credit loss. Includes beneficial interest in securitized financial asset.

+ References

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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), in continuous unrealized loss position for less than 12 months, without allowance for credit loss. Includes beneficial interest in securitized financial asset.

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Number of investments in debt securities measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in continuous unrealized loss position for less than 12 months, without an allowance for credit loss. Includes beneficial interest in securitized financial asset.

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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), in unrealized loss position without allowance for credit loss.

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Number of investments in debt securities measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in unrealized loss position, without allowance for credit loss. Includes beneficial interest in securitized financial asset.

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