Fair value measurements (Tables)

9 Months Ended

Sep. 30, 2014

Fair Value Disclosures [Abstract]

Financial Instruments Measured at Fair Value on Recurring Basis

As of September 30, 2014, financial instruments measured at fair value on a recurring basis are summarized below:

	Level 1	Level 2	Fair value measurements
	($000 omitted)
Investments available-for-sale:
Debt securities:
Municipal	—	55,186	55,186
Corporate	—	303,115	303,115
Foreign	—	170,434	170,434
U.S. Treasury Bonds	—	14,369	14,369
Equity securities	22,509	—	22,509
	22,509	543,104	565,613

As of December 31, 2013, financial instruments measured at fair value on a recurring basis are summarized below:

	Level 1	Level 2	Fair value measurements
	($000 omitted)
Investments available-for-sale:
Debt securities:
Municipal	—	47,252	47,252
Corporate	—	291,832	291,832
Foreign	—	162,367	162,367
U.S. Treasury Bonds	—	15,197	15,197
Equity securities	20,695	—	20,695
	20,695	516,648	537,343