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Securities (Tables) | 12 Months Ended
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Dec. 31, 2015
Securities |
Schedule of amortized cost and fair value of the securities portfolio and corresponding amounts of gross unrealized gains and losses recognized in accumulated other comprehensive loss |
|  |  |  |  | Gross |  | Gross |  |  |
|  | Amortized |  | Unrealized |  | Unrealized |  | Fair
December 31, 2015: |  | Cost |  | Gains |  | Losses |  | Value
Securities Available-for-Sale |  |  |  |  |  |  |  |
U.S. Treasury |  | $ | 1,509 |  | $ | - |  | $ | - |  | $ | 1,509
U.S. government agencies |  |  | 1,683 |  |  | - |  |  | (127) |  |  | 1,556
U.S. government agencies mortgage-backed |  |  | 2,040 |  |  | - |  |  | (44) |  |  | 1,996
States and political subdivisions |  |  | 30,341 |  |  | 285 |  |  | (100) |  |  | 30,526
Corporate bonds |  |  | 30,157 |  |  | - |  |  | (757) |  |  | 29,400
Collateralized mortgage obligations |  |  | 68,743 |  |  | 24 |  |  | (1,847) |  |  | 66,920
Asset-backed securities |  |  | 241,872 |  |  | 74 |  |  | (10,038) |  |  | 231,908
Collateralized loan obligations |  |  | 94,374 |  |  | - |  |  | (2,123) |  |  | 92,251
Total Securities Available-for-Sale |  | $ | 470,719 |  | $ | 383 |  | $ | (15,036) |  | $ | 456,066
Securities Held-to-Maturity |  |  |  |  |  |  |  |  |  |  |  |
U.S. government agency mortgage-backed |  | $ | 36,505 |  | $ | 1,592 |  | $ | - |  | $ | 38,097
Collateralized mortgage obligations |  |  | 211,241 |  |  | 3,302 |  |  | (965) |  |  | 213,578
Total Securities Held-to-Maturity |  | $ | 247,746 |  | $ | 4,894 |  | $ | (965) |  | $ | 251,675
|  |  |  |  | Gross |  | Gross |  |  |
|  | Amortized |  | Unrealized |  | Unrealized |  | Fair
December 31, 2014: |  | Cost |  | Gains |  | Losses |  | Value
Securities Available-for-Sale |  |  |  |  |  |  |  |  |  |  |  |
U.S. Treasury |  | $ | 1,529 |  | $ | - |  | $ | (2) |  | $ | 1,527
U.S. government agencies |  |  | 1,711 |  |  | - |  |  | (87) |  |  | 1,624
States and political subdivisions |  |  | 21,682 |  |  | 432 |  |  | (96) |  |  | 22,018
Corporate bonds |  |  | 31,243 |  |  | 309 |  |  | (567) |  |  | 30,985
Collateralized mortgage obligations |  |  | 65,728 |  |  | 31 |  |  | (2,132) |  |  | 63,627
Asset-backed securities |  |  | 175,565 |  |  | 199 |  |  | (2,268) |  |  | 173,496
Collateralized loan obligations |  |  | 94,236 |  |  | 176 |  |  | (2,203) |  |  | 92,209
Total Securities Available-for-Sale |  | $ | 391,694 |  | $ | 1,147 |  | $ | (7,355) |  | $ | 385,486
Securities Held-to-Maturity |  |  |  |  |  |  |  |  |  |  |  |
U.S. government agency mortgage-backed |  | $ | 37,125 |  | $ | 2,030 |  | $ | - |  | $ | 39,155
Collateralized mortgage obligations |  |  | 222,545 |  |  | 3,005 |  |  | (1,439) |  |  | 224,111
Total Securities Held-to-Maturity |  | $ | 259,670 |  | $ | 5,035 |  | $ | (1,439) |  | $ | 263,266
Schedule of fair value, amortized cost and weighted average yield of debt securities by contractual maturity along with securities not due at a single maturity date, primarily mortgage-backed securities (MBS), asset-backed securities, and collateralized loan obligations |
|  |  |  |  | Weighted |  |  |  |  |
|  | Amortized |  | Average |  |  | Fair |
Securities Available-for-Sale |  | Cost |  | Yield |  |  | Value |
Due in one year or less |  | $ | 17,130 |  | 1.74 | % |  | $ | 17,138 |
Due after one year through five years |  |  | 6,897 |  | 2.92 | % |  |  | 6,959 |
Due after five years through ten years |  |  | 34,843 |  | 2.39 | % |  |  | 34,171 |
Due after ten years |  |  | 4,820 |  | 3.21 | % |  |  | 4,723 |
|  |  | 63,690 |  | 2.33 | % |  |  | 62,991 |
Mortgage-backed and collateralized mortgage obligations |  |  | 70,783 |  | 2.29 | % |  |  | 68,916 |
Asset-backed securities |  |  | 241,872 |  | 1.47 | % |  |  | 231,908 |
Collateralized loan obligations |  |  | 94,374 |  | 3.06 | % |  |  | 92,251 |
|  | $ | 470,719 |  | 2.03 | % |  | $ | 456,066 |
Securities Held-to-Maturity |  |  |  |  |  |  |  |  |  |
Mortgage-backed and collateralized mortgage obligations |  | $ | 247,746 |  | 2.78 | % |  | $ | 251,675 |
Schedule of amortized cost and fair value of securities that exceed 10% of stockholders equity | Information regarding these three issuers and the value of the securities issued follows:
|  | December 31, 2015 |
|  | Amortized |  | Fair |
Issuer |  | Cost |  | Value |
College Loan Corporation |  | $ | 73,293 |  | $ | 70,254 |
Nelnet Student Loan |  |  | 23,359 |  |  | 23,291 |
GCO Education Loan Funding Corp |  |  | 37,508 |  |  | 35,263 |
Schedule of securities with unrealized losses aggregated by investment category and length of time that individual securities have been in a continuous unrealized loss position |
|  | Less than 12 months |  | Greater than 12 months |  |  |  |  |  |  |  |
December 31, 2015 |  | in an unrealized loss position |  | in an unrealized loss position |  | Total
|  | Number of |  | Unrealized |  | Fair |  | Number of |  | Unrealized |  | Fair |  | Number of |  | Unrealized |  | Fair
Securities Available-for-Sale |  | Securities |  | Losses |  | Value |  | Securities |  | Losses |  | Value |  | Securities |  | Losses |  | Value
U.S. government agencies |  | - |  | $ | - |  | $ | - |  | 1 |  | $ | 127 |  | $ | 1,556 |  | 1 |  | $ | 127 |  | $ | 1,556
U.S. government agencies mortgage-backed |  | 1 |  |  | 44 |  |  | 1,996 |  | - |  |  | - |  |  | - |  | 1 |  |  | 44 |  |  | 1,996
States and political subdivisions |  | 2 |  |  | 19 |  |  | 1,541 |  | 1 |  |  | 81 |  |  | 1,713 |  | 3 |  |  | 100 |  |  | 3,254
Corporate bonds |  | 5 |  |  | 292 |  |  | 14,866 |  | 3 |  |  | 465 |  |  | 14,534 |  | 8 |  |  | 757 |  |  | 29,400
Collateralized mortgage obligations |  | 4 |  |  | 334 |  |  | 16,218 |  | 7 |  |  | 1,513 |  |  | 43,618 |  | 11 |  |  | 1,847 |  |  | 59,836
Asset-backed securities |  | 9 |  |  | 2,080 |  |  | 78,301 |  | 8 |  |  | 7,958 |  |  | 121,217 |  | 17 |  |  | 10,038 |  |  | 199,518
Collateralized loan obligations |  | 5 |  |  | 446 |  |  | 29,480 |  | 9 |  |  | 1,677 |  |  | 62,771 |  | 14 |  |  | 2,123 |  |  | 92,251
|  | 26 |  | $ | 3,215 |  | $ | 142,402 |  | 29 |  | $ | 11,821 |  | $ | 245,409 |  | 55 |  | $ | 15,036 |  | $ | 387,811
Securities Held-to-Maturity |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Collateralized mortgage obligations |  | 8 |  | $ | 505 |  | $ | 40,307 |  | 2 |  | $ | 460 |  | $ | 33,842 |  | 10 |  | $ | 965 |  | $ | 74,149
|  | 8 |  | $ | 505 |  | $ | 40,307 |  | 2 |  | $ | 460 |  | $ | 33,842 |  | 10 |  | $ | 965 |  | $ | 74,149
|  | Less than 12 months |  | Greater than 12 months |  |  |  |  |  |  |  |
December 31, 2014 |  | in an unrealized loss position |  | in an unrealized loss position |  | Total
|  | Number of |  | Unrealized |  |  | Fair |  | Number of |  | Unrealized |  |  | Fair |  | Number of |  | Unrealized |  |  | Fair
Securities Available-for-Sale |  | Securities |  | Losses |  |  | Value |  | Securities |  | Losses |  |  | Value |  | Securities |  | Losses |  |  | Value
U.S. Treasury |  | 1 |  | $ | 2 |  | $ | 1,527 |  | - |  | $ | - |  | $ | - |  | 1 |  | $ | 2 |  | $ | 1,527
U.S. government agencies |  | - |  |  | - |  |  | - |  | 1 |  |  | 87 |  |  | 1,624 |  | 1 |  |  | 87 |  |  | 1,624
States and political subdivisions |  | 4 |  |  | 96 |  |  | 4,896 |  | - |  |  | - |  |  | - |  | 4 |  |  | 96 |  |  | 4,896
Corporate bonds |  | 4 |  |  | 486 |  |  | 15,246 |  | 1 |  |  | 81 |  |  | 1,921 |  | 5 |  |  | 567 |  |  | 17,167
Collateralized mortgage obligations |  | 5 |  |  | 900 |  |  | 38,284 |  | 3 |  |  | 1,232 |  |  | 21,604 |  | 8 |  |  | 2,132 |  |  | 59,888
Asset-backed securities |  | 9 |  |  | 1,077 |  |  | 99,286 |  | 3 |  |  | 1,191 |  |  | 43,662 |  | 12 |  |  | 2,268 |  |  | 142,948
Collateralized loan obligations |  | 12 |  |  | 2,203 |  |  | 82,387 |  | - |  |  | - |  |  | - |  | 12 |  |  | 2,203 |  |  | 82,387
|  | 35 |  | $ | 4,764 |  | $ | 241,626 |  | 8 |  | $ | 2,591 |  | $ | 68,811 |  | 43 |  | $ | 7,355 |  | $ | 310,437
Securities Held-to-Maturity |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Collateralized mortgage obligations |  | 7 |  | $ | 457 |  | $ | 49,302 |  | 4 |  | $ | 982 |  | $ | 46,283 |  | 11 |  | $ | 1,439 |  | $ | 95,585
|  | 7 |  | $ | 457 |  | $ | 49,302 |  | 4 |  | $ | 982 |  | $ | 46,283 |  | 11 |  | $ | 1,439 |  | $ | 95,585
Schedule of proceeds from sale and gross realized gains and losses on sale of securities |
|  | Years ended December 31,
|  | 2015 |  | 2014 |  | 2013
Proceeds from sales of securities |  | $ | 70,176 |  | $ | 296,013 |  | $ | 533,302
Gross realized gains on securities |  |  | 106 |  |  | 3,231 |  |  | 5,376
Gross realized losses on securities |  |  | (284) |  |  | (1,512) |  |  | (7,288)
Securities gains (losses), net |  | $ | (178) |  | $ | 1,719 |  | $ | (1,912)
Income tax expense (benefit) on net realized gains (losses) |  | $ | (71) |  | $ | 704 |  | $ | (784)

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