Investment Securities | INVESTMENT SECURITIES | | | | | | | | | | | | | | | | | | | | September 30, | 2011 | | Amortized Cost | | Gross Unrealized | | Fair Value | | Yield | Gains | | Losses | | | (In thousands) | Available-for-sale securities | | | | | | | | | | U.S. government and agency securities due | | | | | | | | | | Within 1 year | $ | 500 |
| | $ | 34 |
| | $ | — |
| | $ | 534 |
| | 4.00 | % | 1 to 5 years | — |
| | — |
| | — |
| | — |
| | — |
| 5 to 10 years | 9,300 |
| | 4,547 |
| | — |
| | 13,847 |
| | 10.38 | % | Over 10 years | 175,515 |
| | 631 |
| | — |
| | 176,146 |
| | 2.57 | % | Corporate bonds due |
| |
| |
| |
| |
| 5 to 10 years | 30,000 |
| | 284 |
| | (325 | ) | | 29,959 |
| | 4.00 | % | Municipal bonds due |
| |
| |
| |
| |
| Over 10 years | 20,461 |
| | 3,107 |
| | — |
| | 23,568 |
| | 6.45 | % | Mortgage-backed securities |
| |
| |
| |
| |
| Agency pass-through certificates | 2,883,734 |
| | 127,356 |
| | — |
| | 3,011,090 |
| | 4.72 | % | | 3,119,510 |
| | 135,959 |
| | (325 | ) | | 3,255,144 |
| | 4.62 | % | Held-to-maturity securities | | | | | | | | | | Tax-exempt municipal bonds due | | | | | | | | | | 1 to 5 years | 405 |
| | 5 |
| | — |
| | 410 |
| | 6.52 | % | 5 to 10 years | 1,545 |
| | 68 |
| | — |
| | 1,613 |
| | 5.60 | % | Over 10 years | — |
| | — |
| | — |
| | — |
| | — | % | U.S. government and agency securities due |
| |
| |
| |
| |
| 1 to 5 years | — |
| | — |
| | — |
| | — |
| | — | % | Mortgage-backed securities |
| |
| |
| |
| |
| Agency pass-through certificates | 45,086 |
| | 3,507 |
| | — |
| | 48,593 |
| | 5.31 | % | | 47,036 |
| | 3,580 |
| | — |
| | 50,616 |
| | 5.33 | % | | $ | 3,166,546 |
| | $ | 139,539 |
| | $ | (325 | ) | | $ | 3,305,760 |
| | 4.63 | % | | | | | | | | | | |
| | | | | | | | | | | | | | | | | | | | September 30, | 2010 | | Amortized Cost | | Gross Unrealized | | Fair Value | | Yield | | Gains | | Losses | | | (In thousands) | Available-for-sale securities | | | | | | | | | | U.S. government and agency securities due | | | | | | | | | | Within 1 year | $ | 500 |
| | $ | 26 |
| | $ | — |
| | $ | 526 |
| | 4.00 | % | 1 to 5 years | 25,000 |
| | 180 |
| | — |
| | 25,180 |
| | 3.25 | % | 5 to 10 years | 158,915 |
| | 5,344 |
| | (105 | ) | | 164,154 |
| | 3.59 | % | Over 10 years | 150,000 |
| | 1,161 |
| | (15 | ) | | 151,146 |
| | 3.50 | % | Corporate bonds due | | | | | | | | | | 5 to 10 years | 10,000 |
| | — |
| | — |
| | 10,000 |
| | 6.00 | % | Mortgage-backed securities | | | | | | | | | | Agency pass-through certificates | 2,058,130 |
| | 72,853 |
| | (896 | ) | | 2,130,087 |
| | 5.26 | % | | 2,402,545 |
| | 79,564 |
| | (1,016 | ) | | 2,481,093 |
| | 5.02 | % | Held-to-maturity securities | | | | | | | | | | Tax-exempt municipal bonds due | | | | | | | | | | 1 to 5 years | 1,105 |
| | 65 |
| | — |
| | 1,170 |
| | 6.11 | % | 5 to 10 years | 1,940 |
| | 115 |
| | — |
| | 2,055 |
| | 5.67 | % | Over 10 years | 4,010 |
| | 34 |
| | — |
| | 4,044 |
| | 5.60 | % | U.S. government and agency securities due | | | | | | | | | | 1 to 5 years | — |
| | — |
| | — |
| | — |
| | — | % | Mortgage-backed securities | | | | | | | | | | Agency pass-through certificates | 73,052 |
| | 4,579 |
| | — |
| | 77,631 |
| | 5.59 | % | | 80,107 |
| | 4,793 |
| | — |
| | 84,900 |
| | 5.60 | % | | $ | 2,482,652 |
| | $ | 84,357 |
| | $ | (1,016 | ) | | $ | 2,565,993 |
| | 5.04 | % |
$131,361,000 of available-for-sale securities were sold in 2011, resulting in a gain of $8,147,000. $496,024,000 of available-for-sale securities were sold in 2010, resulting in a net gain of $22,409,000. $18,453,000 of available-for-sale securities were sold in 2009, resulting in a net gain of $1,063,000.
Substantially all mortgage-backed securities have contractual due dates that exceed ten years.
The following table shows the unrealized gross losses and fair value of securities at September 30, 2011, by length of time that individual securities in each category have been in a continuous loss position. The Company had no securities in a continuous loss position for 12 or more months at September 30, 2011, which consisted of mortgage-backed securities. Management believes that the declines in fair value of these investments are not an other than temporary impairment. | | | | | | | | | | | | | | | | | | | | As of September 30, | 2011 | | Less than 12 months | 12 months or more | Total | | Unrealized Gross Losses | Fair Value | Unrealized Gross Losses | Fair Value | Unrealized Gross Losses | Fair Value | | (In thousands) | U.S. agency securities | $ | (325 | ) | $ | 9,675 |
| $ | — |
| $ | — |
| $ | (325 | ) | $ | 9,675 |
| Agency pass-through certificates | — |
| — |
| — |
| — |
| — |
| — |
| | $ | (325 | ) | $ | 9,675 |
| $ | — |
| $ | — |
| $ | (325 | ) | $ | 9,675 |
|
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