Marketable Securities

3 Months Ended

Mar. 31, 2013

Marketable Securities [Abstract]

Marketable Securities [Table Text Block]

Marketable Securities

All marketable securities were classified as held-to-maturity for the dates presented and the carrying amounts of held-to-maturity securities were as follows:

(in thousands)	March 31, 2013		December 31, 2012		March 31, 2012
U.S. Government and agency obligations	$	6,169	$	7,375	$	35,123
Commercial paper	29,976		34,966		24,988
Municipal bonds	8,696		8,738		2,052
Corporate bonds	—		5,009		8,281
Total short-term marketable securities	44,841		56,088		70,444
U.S. Government and agency obligations	57,958		55,342		61,247
Municipal bonds	—		—		8,867
Total long-term marketable securities	57,958		55,342		70,114
Total marketable securities	$	102,799	$	111,430	$	140,558

Scheduled maturities of held-to-maturity investments were as follows (in thousands):

March 31, 2013
Due within one year	$	44,841
Due in one to five years	57,958
Total	$	102,799