Fair-Value Measurements (Tables)

3 Months Ended

Mar. 31, 2013

Fair Value Disclosures [Abstract]

Summary Of Valuation Of Financial Instruments At Fair-Value

	March 31, 2013
(Dollars in thousands)	Total		Level 1		Level 2		Level 3
Cash equivalents	$	345,784	$	64,592	$	281,192	$	—

	December 31, 2012
(Dollars in thousands)	Total		Level 1		Level 2		Level 3
Cash equivalents	$	378,266	$	70,488	$	307,778	$	—
Current marketable securities	3,200		—		3,200		—