XML 47 R29.htm IDEA: XBRL DOCUMENT v3.22.2
Securities (Tables)
 6 Months Ended
Jun. 30, 2022
Investments, Debt and Equity Securities [Abstract]  
Debt Securities, Held-to-maturity [Table Text Block] A summary of the amortized cost, fair value and allowance for credit losses related to securities held to maturity as of June 30, 2022 and December 31, 2021 is presented below.
Amortized
Cost		Gross
Unrealized
Gains		Gross
Unrealized
Losses		Estimated
Fair Value		Allowance
for Credit
Losses		Net
Carrying
Amount
June 30, 2022
Residential mortgage-backed securities
$526,675 $— $40,383 $486,292 $— $526,675 
States and political subdivisions
1,418,411 3,956 81,583 1,340,784 (158)1,418,253 
Other1,500 — 61 1,439 — 1,500 
Total$1,946,586 $3,956 $122,027 $1,828,515 $(158)$1,946,428 
December 31, 2021
Residential mortgage-backed securities
$527,264 $18,766 $— $546,030 $— $527,264 
States and political subdivisions
1,220,573 41,141 101 1,261,613 (158)1,220,415 
Other1,500 — — 1,500 — 1,500 
Total$1,749,337 $59,907 $101 $1,809,143 $(158)$1,749,179 
Moody's and Standard & Poor's Bond Ratings [Table Text Block]
The following table summarizes Moody's and/or Standard & Poor's bond ratings for our portfolio of held-to-maturity securities issued by States and political subdivisions and other securities as of June 30, 2022 and December 31, 2021:
States and Political Subdivisions
Not Guaranteed or Pre-RefundedGuaranteed by the Texas PSFPre-RefundedTotalOther
Securities
June 30, 2022
Aaa/AAA$161,274 $764,405 $344,335 $1,270,014 $— 
Aa/AA148,397 — — 148,397 — 
Not rated— — — — 1,500 
Total$309,671 $764,405 $344,335 $1,418,411 $1,500 
December 31, 2021
Aaa/AAA$92,379 $460,648 $563,251 $1,116,278 $— 
Aa/AA
104,295 — — 104,295 — 
Not rated— — — — 1,500 
Total$196,674 $460,648 $563,251 $1,220,573 $1,500 
Debt Securities, Held-to-maturity, Allowance for Credit Loss [Table Text Block]
The following table details activity in the allowance for credit losses on held-to-maturity securities during the three and six months ended June 30, 2022 and 2021.
Three Months Ended
June 30,		Six Months Ended
June 30,
2022202120222021
Beginning balance$158 $158 $158 $160 
Credit loss expense (benefit)— — — (2)
Ending balance$158 $158 $158 $158 
Amortized Cost, Estimated Fair Value and Allowance for Credit Losses of Securities Available for Sale A summary of the amortized cost, fair value and allowance for credit losses related to securities available for sale as of June 30, 2022 and December 31, 2021 is presented below.
Amortized
Cost		Gross
Unrealized
Gains		Gross
Unrealized
Losses		Allowance
for Credit
Losses		Estimated
Fair Value
June 30, 2022
U.S. Treasury$4,656,896 $2,093 $242,690 $— $4,416,299 
Residential mortgage-backed securities
5,967,803 3,443 635,521 — 5,335,725 
States and political subdivisions
7,183,199 50,465 246,368 — 6,987,296 
Other42,365 — — — 42,365 
Total$17,850,263 $56,001 $1,124,579 $— $16,781,685 
December 31, 2021
U.S. Treasury$2,165,702 $23,333 $9,602 $— $2,179,433 
Residential mortgage-backed securities
4,059,692 31,662 25,089 — 4,066,265 
States and political subdivisions
7,178,135 463,810 5,374 — 7,636,571 
Other42,359 — — — 42,359 
Total$13,445,888 $518,805 $40,065 $— $13,924,628 
Securities, with Unrealized Losses Segregated by Length of Impairment
The table below summarizes, as of June 30, 2022, securities available for sale in an unrealized loss position for which an allowance for credit losses has not been recorded, aggregated by type of security and length of time in a continuous unrealized loss position.
Less than 12 MonthsMore than 12 MonthsTotal
Estimated
Fair Value		Unrealized
Losses		Estimated
Fair Value		Unrealized
Losses		Estimated
Fair Value		Unrealized
Losses
U.S. Treasury$4,224,018 $242,690 $— $— $4,224,018 $242,690 
Residential mortgage-backed securities4,825,871 568,405 369,098 67,116 5,194,969 635,521 
States and political subdivisions3,249,625 241,884 13,824 4,484 3,263,449 246,368 
Total$12,299,514 $1,052,979 $382,922 $71,600 $12,682,436 $1,124,579 
Amortized Cost and Estimated Fair Value of Securities, Excluding Trading Securities, Presented by Contractual Maturity The following table summarizes the maturity distribution schedule of securities held to maturity and securities available for sale as of June 30, 2022. Mortgage-backed securities are included in maturity categories based on their stated maturity date. Expected maturities may differ from contractual maturities because issuers may have the right to call or prepay obligations. Other securities classified as available for sale include stock in the Federal Reserve Bank and the Federal Home Loan Bank, which have no maturity date. These securities have been included in the total column only.
Within 1 Year1 - 5 Years5 - 10 YearsAfter 10 YearsTotal
Held To Maturity
Amortized Cost
Residential mortgage-backed securities$3 $— $514,582 $12,090 $526,675 
States and political subdivisions350,365 84,053 22,102 961,891 1,418,411 
Other— 1,500 — — 1,500 
Total$350,368 $85,553 $536,684 $973,981 $1,946,586 
Estimated Fair Value
Residential mortgage-backed securities$3 $— $475,721 $10,568 $486,292 
States and political subdivisions351,237 84,787 22,166 882,594 1,340,784 
Other— 1,439 — — 1,439 
Total$351,240 $86,226 $497,887 $893,162 $1,828,515 
Available For Sale
Amortized Cost
U. S. Treasury$— $3,031,706 $1,433,320 $191,870 $4,656,896 
Residential mortgage-backed securities55 11,080 18,743 5,937,925 5,967,803 
States and political subdivisions207,078 1,546,995 902,953 4,526,173 7,183,199 
Other— — — — 42,365 
Total$207,133 $4,589,781 $2,355,016 $10,655,968 $17,850,263 
Estimated Fair Value
U. S. Treasury$— $2,957,018 $1,301,539 $157,742 $4,416,299 
Residential mortgage-backed securities55 11,231 18,792 5,305,647 5,335,725 
States and political subdivisions209,138 1,579,097 893,132 4,305,929 6,987,296 
Other— — — — 42,365 
Total$209,193 $4,547,346 $2,213,463 $9,769,318 $16,781,685 
Investment Income Premium amortization and discount accretion included in interest income on securities was as follows:
Three Months Ended
June 30,		Six Months Ended
June 30,
2022202120222021
Premium amortization$(28,053)$(30,541)$(57,113)$(61,776)
Discount accretion2,482 705 3,888 1,342 
Net (premium amortization) discount accretion$(25,571)$(29,836)$(53,225)$(60,434)
Trading Account Securities, at Estimated Fair Value Trading account securities, at estimated fair value, were as follows:
June 30,
2022		December 31,
2021
U.S. Treasury$24,615 $24,237 
States and political subdivisions65 925 
Total$24,680 $25,162 
Net Gains and Losses on Trading Account Securities
Net gains and losses on trading account securities were as follows:
Three Months Ended
June 30,		Six Months Ended
June 30,
2022202120222021
Net gain on sales transactions$1,012 $293 $1,352 $402 
Net mark-to-market gains (losses)(76)— (244)(69)
Net gain (loss) on trading account securities$936 $293 $1,108 $333