2013 | |||||||||||||||||||||||
Less than 12 Months | 12 Months or More | Total | |||||||||||||||||||||
Fair Value | Unrealized Losses | Fair Value | Unrealized Losses | Fair Value | Unrealized Losses | ||||||||||||||||||
U.S. Treasury and agency debt securities | $ | 221,548 | $ | (353 | ) | $ | — | $ | — | $ | 221,548 | $ | (353 | ) | |||||||||
Corporate and other debt securities | 106,485 | (243 | ) | — | — | 106,485 | (243 | ) | |||||||||||||||
Asset-backed securities | 84,051 | (333 | ) | 5,048 | (58 | ) | 89,099 | (391 | ) | ||||||||||||||
Municipal debt securities | 10,702 | (34 | ) | 1,019 | (6 | ) | 11,721 | (40 | ) | ||||||||||||||
Mutual funds | — | — | 20,183 | (1,849 | ) | 20,183 | (1,849 | ) | |||||||||||||||
Total | $ | 422,786 | $ | (963 | ) | $ | 26,250 | $ | (1,913 | ) | $ | 449,036 | $ | (2,876 | ) |
2012 | |||||||||||||||||||||||
Less than 12 Months | 12 Months or More | Total | |||||||||||||||||||||
Fair Value | Unrealized Losses | Fair Value | Unrealized Losses | Fair Value | Unrealized Losses | ||||||||||||||||||
U.S. Treasury and agency debt securities | $ | 120,118 | $ | (53 | ) | $ | — | $ | — | $ | 120,118 | $ | (53 | ) | |||||||||
Corporate and other debt securities | 25,662 | (21 | ) | 699 | (1 | ) | 26,361 | (22 | ) | ||||||||||||||
Asset-backed securities | 27,180 | (93 | ) | 1,499 | (36 | ) | 28,679 | (129 | ) | ||||||||||||||
Municipal debt securities | 7,908 | (32 | ) | 696 | (35 | ) | 8,604 | (67 | ) | ||||||||||||||
Mutual funds | 21,150 | (433 | ) | — | — | 21,150 | (433 | ) | |||||||||||||||
Total | $ | 202,018 | $ | (632 | ) | $ | 2,894 | $ | (72 | ) | $ | 204,912 | $ | (704 | ) |