Debt securities available-for-sale (Tables)	3 Months Ended
Debt securities available-for-sale (Tables)	Mar. 31, 2023
Investments [Abstract]
Debt Securities, Available-For-Sale	At March 31, 2023 Gross Gross Weighted Amortized unrealized unrealized Fair average (In thousands) cost gains losses value yield U.S. Treasury securities Within 1 year $ 4,724,780 $ 622 $ 50,140 $ 4,675,262 2.69 % After 1 to 5 years 5,991,694 43 308,049 5,683,688 1.33 After 5 to 10 years 308,525 - 32,728 275,797 1.63 Total U.S. Treasury securities 11,024,999 665 390,917 10,634,747 1.92 Collateralized mortgage obligations - federal agencies After 1 to 5 years 13,109 - 733 12,376 1.58 After 5 to 10 years 34,671 - 2,230 32,441 1.80 After 10 years 123,200 34 9,279 113,955 2.56 Total collateralized mortgage obligations - federal agencies 170,980 34 12,242 158,772 2.33 Mortgage-backed securities Within 1 year 460 - 3 457 3.37 After 1 to 5 years 71,211 14 2,721 68,504 2.36 After 5 to 10 years 837,061 47 52,682 784,426 2.19 After 10 years 6,610,019 1,220 1,086,066 5,525,173 1.63 Total mortgage-backed securities 7,518,751 1,281 1,141,472 6,378,560 1.70 Other After 1 to 5 years 1,049 - - 1,049 3.98 Total other 1,049 - - 1,049 3.98 Total debt securities available-for-sale [1] $ 18,715,779 $ 1,980 $ 1,544,631 $ 17,173,128 1.84 % [1] Includes $ 10.3 billion pledged to secure government and trust deposits, assets sold under agreements to repurchase, credit facilities and loan servicing agreements that the secured parties are not permitted to sell or repledge the collateral, of which $ 9.4 billion serve as collateral for public funds. The Corporation had unpledged Available for Sale securities with a fair value of $ 6.7 billion that could be used to increase its borrowing facilities. At December 31, 2022 Gross Gross Weighted Amortized unrealized unrealized Fair average (In thousands) cost gains losses value yield U.S. Treasury securities Within 1 year $ 4,576,127 $ 506 $ 47,156 $ 4,529,477 2.42 % After 1 to 5 years 6,793,739 - 410,858 6,382,881 1.35 After 5 to 10 years 308,854 - 40,264 268,590 1.63 Total U.S. Treasury securities 11,678,720 506 498,278 11,180,948 1.78 Collateralized mortgage obligations - federal agencies After 1 to 5 years 3,914 - 213 3,701 1.77 After 5 to 10 years 47,979 - 3,428 44,551 1.73 After 10 years 127,639 24 10,719 116,944 2.53 Total collateralized mortgage obligations - federal agencies 179,532 24 14,360 165,196 2.30 Mortgage-backed securities After 1 to 5 years 74,328 11 3,428 70,911 2.33 After 5 to 10 years 866,757 43 58,997 807,803 2.16 After 10 years 6,762,150 932 1,184,626 5,578,456 1.61 Total mortgage-backed securities 7,703,235 986 1,247,051 6,457,170 1.68 Other After 1 to 5 years 1,062 - 2 1,060 3.98 Total other 1,062 - 2 1,060 3.98 Total debt securities available-for-sale [1] $ 19,562,549 $ 1,516 $ 1,759,691 $ 17,804,374 1.75 % [1] Includes $ 11.3 billion pledged to secure government and trust deposits, assets sold under agreements to repurchase, credit facilities and loan servicing agreements that the secured parties are not permitted to sell or repledge the collateral, of which $ 10.3 billion serve as collateral for public funds. The Corporation had unpledged Available for Sale securities with a fair value of $ 6.4 billion that could be used to increase its borrowing facilities.
Debt Securities Available For Sale Unrealized Loss Position Fair Value	At March 31, 2023 Less than 12 months 12 months or more Total Gross Gross Gross Fair unrealized Fair unrealized Fair unrealized (In thousands) value losses value losses value losses U.S. Treasury securities $ 2,162,329 $ 42,295 $ 6,598,099 $ 348,622 $ 8,760,428 $ 390,917 Collateralized mortgage obligations - federal agencies 42,946 1,526 113,220 10,716 156,166 12,242 Mortgage-backed securities 440,122 22,396 5,881,221 1,119,076 6,321,343 1,141,472 Total debt securities available-for-sale in an unrealized loss position $ 2,645,397 $ 66,217 $ 12,592,540 $ 1,478,414 $ 15,237,937 $ 1,544,631 At December 31, 2022 Less than 12 months 12 months or more Total Gross Gross Gross Fair unrealized Fair unrealized Fair unrealized (In thousands) value losses value losses value losses U.S. Treasury securities $ 6,027,786 $ 288,582 $ 3,244,572 $ 209,696 $ 9,272,358 $ 498,278 Collateralized mortgage obligations - federal agencies 139,845 10,655 22,661 3,705 162,506 14,360 Mortgage-backed securities 1,740,214 138,071 4,662,195 1,108,980 6,402,409 1,247,051 Other 60 2 - - 60 2 Total debt securities available-for-sale in an unrealized loss position $ 7,907,905 $ 437,310 $ 7,929,428 $ 1,322,381 $ 15,837,333 $ 1,759,691