Concentration of Credit Risk and Fair Value of Financial Assets and Liabilities (Tables)

9 Months Ended

Sep. 30, 2013

CONCENTRATION OF CREDIT RISK AND FAIR VALUE OF FINANCIAL ASSETS AND FINANCIAL LIABILITIES: [Abstract]

Fair Value, Measurement Inputs, Disclosure [Table Text Block]

Our financial assets that are accounted for at fair value on a recurring basis are presented in the tables below as of September 30, 2013 and December 31, 2012 (in thousands):

	Fair Value as of September 30, 2013
	Level 1		Level 2		Level 3		Total
Assets:
Money market and demand accounts (a)	$	518,352	$	—	$	—	$	518,352
Commercial paper (b)	—		188,060		—		188,060
U.S. government securities	—		37,463		—		37,463
Corporate bonds, asset backed and other securities	1,766		11,201		—		12,967
	$	520,118	$	236,724	$	—	$	756,842

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(a) Included within cash and cash equivalents.

(b) Includes $37.2 million of commercial paper that is included within cash and cash equivalents.

	Fair Value as of December 31, 2012
	Level 1		Level 2		Level 3		Total
Assets:
Money market and demand accounts (a)	$	261,899	$	—	$	—	$	261,899
Mutual and exchange traded funds	100,682		—		—		100,682
Commercial paper (b)	—		150,868		—		150,868
U.S. government securities	—		50,560		—		50,560
Corporate bonds, asset backed and other securities	—		13,270		—		13,270
	$	362,581	$	214,698	$	—	$	577,279

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(a) Included within cash and cash equivalents.

(b) Includes $87.9 million of commercial paper that is included within cash and cash equivalents.