Fair value measurements (Tables)

9 Months Ended

Sep. 30, 2013

Financial Instruments Measured at Fair Value on Recurring Basis

As of September 30, 2013, financial instruments measured at fair value on a recurring basis are summarized below:

	Level 1		Level 2		Fair value measurements
	($000 omitted)
Short-term investments		37,274		—		37,274
Investments available-for-sale:
Debt securities:
Municipal		—		47,396		47,396
Corporate and utilities		—		285,356		285,356
Foreign		—		167,174		167,174
U.S. Government		—		15,327		15,327
Equity securities		17,171		—		17,171
		54,445		515,253		569,698

As of December 31, 2012, financial instruments measured at fair value on a recurring basis are summarized below:

	Level 1		Level 2		Fair value measurements
	($000 omitted)
Short-term investments		37,025		—		37,025
Investments available-for-sale:
Debt securities:
Municipal		—		19,011		19,011
Corporate and utilities		—		287,528		287,528
Foreign		—		169,009		169,009
U.S. Government		—		16,638		16,638
Equity securities		11,073		—		11,073
		48,098		492,186		540,284