Fair Value Measurements (Table)

12 Months Ended

Dec. 31, 2013

Fair Value Disclosures

Fair value measurements

			December 31, 2013				December 31, 2012
		Level within the Fair Value Hierarchy	Book Value			Fair Value	Book Value		Fair Value
(Dollars in thousands)
Cash and cash equivalents		1	$	342,065	$	342,065	$	378,358	$	378,358
Short-term investments
	U.S. Treasury Notes	1		50,104		50,104		100,676		100,676
Long-term investments
	U.S. Treasury Notes	1		-		-		50,305		50,339
Long-term debt
	6.95% Senior Notes	1		342,000		309,852		342,000		376,610
	6.7% Senior Notes	2		532,449		507,697		532,194		582,744