XML 20 R37.htm IDEA: XBRL DOCUMENT v2.4.0.6
Fair Value Measurements (Details 2) (Recurring [Member], Level 3 [Member], Failed Auction Securities [Member], USD $)
In Thousands, unless otherwise specified
3 Months Ended
Mar. 31, 2013
Recurring [Member] | Level 3 [Member] | Failed Auction Securities [Member]
 
Change in the estimated fair values calculated for those assets valued on a recurring basis utilizing Level 3 inputs  
Balance at the beginning of the period $ 4,979
Credit gain on available-for-sale securities included in Other income (expense), net 1
Unrealized gain included in Other comprehensive income (loss) 51
Balance at the end of the period $ 5,031