Marketable Securities	3 Months Ended
Mar. 31, 2014
Marketable Securities [Abstract]
Marketable Securities	Marketable Securities Marketable securities consist primarily of corporate bonds and certificates of deposit with maturities greater than three months and up to ten years at the time of purchase as well as marketable equity securities. These securities, which are classified as available-for-sale, are carried at fair value, with unrealized gains and losses, net of any tax effect, reported in stockholders’ equity as accumulated other comprehensive income (loss). For the three months ended March 31, 2014, gains of $2 were reclassified from accumulated other comprehensive income and recognized in the income statement in other income compared to losses of $89 for the comparable period in 2013. These securities are classified as current and non-current marketable securities based upon their maturities. Amortization of premiums and discounts is included in interest income. For the three months ended March 31, 2014, the amortization of bond premiums totals $137 compared to $187 for the comparable period in 2013. The values of these securities may fluctuate as a result of changes in equity values, market interest rates and credit risk.

Marketable Securities

Marketable securities consist primarily of corporate bonds and certificates of deposit with maturities greater than three months and up to ten years at the time of purchase as well as marketable equity securities. These securities, which are classified as available-for-sale, are carried at fair value, with unrealized gains and losses, net of any tax effect, reported in stockholders’ equity as accumulated other comprehensive income (loss). For the three months ended March 31, 2014, gains of $2 were reclassified from accumulated other comprehensive income and recognized in the income statement in other income compared to losses of $89 for the comparable period in 2013. These securities are classified as current and non-current marketable securities based upon their maturities. Amortization of premiums and discounts is included in interest income. For the three months ended March 31, 2014, the amortization of bond premiums totals $137 compared to $187 for the comparable period in 2013. The values of these securities may fluctuate as a result of changes in equity values, market interest rates and credit risk.