December 31, 2013 | ||||||||
(Millions of dollars) | Cost Basis | Fair Value | ||||||
Due in one year or less | $ | 187 | $ | 188 | ||||
Due after one year through five years | 572 | 592 | ||||||
Due after five years through ten years | 24 | 25 | ||||||
Due after ten years | 30 | 30 | ||||||
U.S. governmental agency mortgage-backed securities | 322 | 321 | ||||||
Residential mortgage-backed securities | 18 | 18 | ||||||
Commercial mortgage-backed securities | 87 | 93 | ||||||
Total debt securities – available-for-sale | $ | 1,240 | $ | 1,267 | ||||