Fair Value of Financial Instruments (Tables)

3 Months Ended

Mar. 31, 2012

Schedule of Fair value of Cash, Cash Equivalents and Short Term investments, by Balance Sheet Grouping

Cash, cash equivalents and short-term investments consist of the following:

	March 31, 2012				December 31, 2011
	Cost		Fair Value		Cost		Fair Value
Cash and Cash Equivalents:
Cash and overnight deposits	$	444,914	$	444,914	$	445,586	$	445,586
Corporate commercial paper	853,302		853,734		791,729		791,902
Time deposits	114,699		114,699		57,041		57,041
Total cash and cash equivalents	1,412,915		1,413,347		1,294,356		1,294,529
Short-Term Investments:
Time deposits	16,277		16,277		472		472
Total	$	1,429,192	$	1,429,624	$	1,294,828	$	1,295,001