Derivatives (Tables)

12 Months Ended

Dec. 31, 2012

Derivative Instruments and Hedging Activities Disclosure [Abstract]

Schedule of Derivative Instruments

The following table provides a detail of the swaps outstanding and the related hedged items as of December 31, 2012:

		Face value of medium-term notes	Aggregate notional amount of interest rate swaps		Weighted-average variable interest rate on hedged debt as of December 31,
Issuance date	Maturity date			Fixed interest rate	2012	2011
		(Dollars in thousands)
May 2011	June 2017	$350,000	$150,000	3.50%	1.62%	1.84%
February 2011	March 2015	$350,000	$150,000	3.15%	1.66%	1.43%
February 2008	March 2013	$250,000	$250,000	6.00%	2.84%	2.61%

Impact on the Consolidated Condensed Statements of Earnings related to Fair Value Hedges

The location and amount of gains (losses) on derivative instruments and related hedged items reported in the Consolidated Statements of Earnings were as follows:

	Location of Gain (Loss) Recognized in Income	December 31,
Fair Value Hedging Relationship		2012			2011		2010
		(In thousands)
Derivative: Interest rate swap	Interest expense	$	(5,118	)	6,414		3,328
Hedged item: Fixed-rate debt	Interest expense	5,118			(6,414	)	(3,328	)
Total		$	—		—		—