Investments in Securities and Other Assets | INVESTMENTS IN SECURITIES The available-for-sale portfolio consisted of the following as of June 30, 2015 and December 31, 2014 (in thousands): June 30, 2015 Asset Type Amortized Cost Gross Unrealized Loss Gross Unrealized Gain Fair Value Fannie Mae Certificates Fixed Rate $ 12,560,911 $ (48,682 ) $ 95,893 $ 12,608,122 ARMs 289,626 (1,216 ) 3,087 291,497 Total Fannie Mae 12,850,537 (49,898 ) 98,980 12,899,619 Freddie Mac Certificates Fixed Rate 980,087 (1,258 ) 16,105 994,934 ARMs 65,578 (529 ) 1,157 66,206 Total Freddie Mac 1,045,665 (1,787 ) 17,262 1,061,140 Ginnie Mae Certificates - ARMs 54,201 ā 1,420 55,621 U.S. Treasuries 222,837 ā 1,073 223,910 Total $ 14,173,240 $ (51,685 ) $ 118,735 $ 14,240,290 December 31, 2014 Fannie Mae Certificates Fixed Rate $ 11,356,717 $ (2,984 ) $ 158,570 $ 11,512,303 ARMs 1,282,065 (13,144 ) 4,449 1,273,370 Total Fannie Mae 12,638,782 (16,128 ) 163,019 12,785,673 Freddie Mac Certificates Fixed Rate 1,183,764 ā 25,769 1,209,533 ARMs 394,726 (6,753 ) 1,144 389,117 Total Freddie Mac 1,578,490 (6,753 ) 26,913 1,598,650 Ginnie Mae Certificates - ARMs 66,390 ā 1,743 68,133 U.S. Treasuries 149,585 (534 ) ā 149,051 Total $ 14,433,247 $ (23,415 ) $ 191,675 $ 14,601,507 The following table presents the gross unrealized loss and fair values of our available-for-sale Agency RMBS by length of time that such securities have been in a continuous unrealized loss position as of June 30, 2015 and December 31, 2014 (in thousands): Unrealized loss positions for Less than 12 Months Greater than 12 months Total As of Fair value Unrealized loss Fair value Unrealized loss Fair value Unrealized loss June 30, 2015 $ 5,001,845 $ (50,515 ) $ 93,313 $ (1,170 ) $ 5,095,158 $ (51,685 ) December 31, 2014 259,291 (577 ) 1,494,884 (22,838 ) 1,754,175 (23,415 ) The following table summarizes our net realized gain (loss) from the sale of available-for-sale investments for the three and six months ended June 30, 2015 and 2014 (in thousands): Three Months Ended June 30, Six Months Ended June 30, 2015 2014 2015 2014 Available-for-sale investments, at cost $ 7,338,701 $ 6,380,082 $ 13,338,664 $ 14,151,496 Proceeds from available-for-sale investments sold 7,348,136 6,413,200 13,366,352 14,201,284 Net gain on sale of available-for-sale investments $ 9,435 $ 33,118 27,688 49,788 Gross gain on sale of available-for-sale investments $ 28,403 $ 40,495 62,382 91,637 Gross loss on sale of available-for-sale investments (18,968 ) (7,377 ) (34,694 ) (41,849 ) Net gain on sale of available-for-sale investments $ 9,435 $ 33,118 $ 27,688 $ 49,788 The components of the carrying value of available-for-sale securities at June 30, 2015 and December 31, 2014 are presented below. A premium purchase price is due to the average coupon interest rates on these investments being higher than prevailing market rates; similarly, a discount purchase price is due to the average coupon interest rate on these investments being lower than prevailing market rates. (in thousands) June 30, 2015 December 31, 2014 Principal balance $ 13,630,326 $ 13,880,953 Unamortized premium 545,216 552,869 Unamortized discount (2,302 ) (575 ) Gross unrealized gains 118,735 191,675 Gross unrealized losses (51,685 ) (23,415 ) Fair value $ 14,240,290 $ 14,601,507 The weighted-average coupon interest rate on the Company's Debt Securities as of June 30, 2015 and December 31, 2014 was 3.40% and 3.39% , respectively. Actual maturities of Agency RMBS are generally shorter than stated contractual maturities (which range up to 30 years), because they are affected by the contractual lives of the underlying mortgages, periodic payments and principal prepayments. As of June 30, 2015 , the range of final contractual maturity of the Companyās Agency RMBS portfolio was between 2024 and 2045 and the final maturity of the Company's U.S. Treasuries was between 2019 and 2020 . As of December 31, 2014 , the range of final contractual maturity of the Companyās Agency RMBS portfolio was between 2024 and 2045 the final maturity of the Company's U.S. Treasuries was 2019 . Credit Risk The Company believes it has minimal exposure to credit losses on its investment securities assets at June 30, 2015 and December 31, 2014 because it owns principally Debt Securities. Principal and interest payments on Agency RMBS are guaranteed by Freddie Mac and Fannie Mae, while principal and interest payments on Ginnie Mae RMBS and U.S. Treasuries are backed by the full faith and credit of the U.S. government. In September 2008, both Freddie Mac and Fannie Mae were placed in the conservatorship of the U.S. government. On August 5, 2011, Standard & Poorās ("S&P") downgraded the U.S. governmentās credit rating for the first time to AA+. Fitch Ratings Inc. ("Fitch") announced on October 15, 2013 that it had placed the U.S. government's credit rating on "negative watch". This was changed to "stable" on March 21, 2014. As of June 30, 2015, S&P maintains a AA+ rating, while Fitch and Moody's rate the U.S. government AAA and Aaa, respectively. Because Fannie Mae and Freddie Mac remain under U.S. government conservatorship, the implied credit ratings of Agency RMBS are similarly rated. While the conservatorship, ratings downgrade and ratings watch appear not to have had a significant impact on the fair value of the Agency RMBS or U.S. Treasuries in the Companyās portfolio, these developments increase the uncertainty regarding the credit risk of Debt Securities. |