Short -Term Investment

12 Months Ended

Dec. 31, 2012

Short -Term Investments [Abstract]

SHORT-TERM INVESTMENTS

(2) SHORT-TERM INVESTMENTS

We classify all of our short term investments as available-for-sale. We carry these at fair value and report unrealized gains and losses, net of taxes, in other comprehensive income until realized. These gains and losses are reflected as a separate component of shareholders’ equity in our consolidated balance sheets and our consolidated statements of shareholders’ equity. Cost, gains, and losses are determined using the specific identification method. In the years ended December 31, 2012, 2011, and 2010, we received proceeds from the sales of these securities of $249.0 million, $282.7 million, and $375.5 million, respectively. Gains and losses on these sales were negligible.

Investments consisted of the following as of December 31, 2012:

	Cost Basis		Unrealized Gains		Unrealized Losses			Fair Value
	(Thousands of dollars)
Short-term investments:
Money Market Mutual Funds	$	29,816	$	—	$	—		$	29,816
Commercial Paper		5,494		1		(2	)		5,493
Corporate bonds and notes		29,986		2		(11	)		29,977
Subtotal		65,296		3		(13	)		65,286
Deferred compensation plan assets included in other assets		2,687		—		—			2,687
Total	$	67,983	$	3	$	(13	)	$	67,973

$14.7 million of our investments are long-term and included on the balance sheet as Restricted investments as they are securing outstanding letters of credit with maturities beyond one year.

Investments consisted of the following as of December 31, 2011:

	Cost Basis		Unrealized Gains		Unrealized Losses			Fair Value
	(Thousands of dollars)
Short-term investments:
Money Market Mutual Funds	$	47,140	$	—	$	—		$	47,140
Commercial Paper		15,690		—		(12	)		15,678
Corporate bonds and notes		37,299		26		(116	)		37,209
Subtotal		100,129		26		(128	)		100,027
Deferred compensation plan assets included in other assets		2,807		—		—			2,807
Total	$	102,936	$	26	$	(128	)	$	102,834

The following table presents the cost and fair value of our debt investments based on maturities as of December 31,

	2012				2011
	Amortized Costs		Fair Value		Amortized Costs		Fair Value
	(Thousands of dollars)
Due in one year or less	$	35,480	$	35,470	$	49,667	$	49,569
Due within two years		—		—		3,322		3,318
Total	$	35,480	$	35,470	$	52,989	$	52,887

The following table presents the average coupon rate percentage and the average days to maturity of our debt investments as of December 31,

	2012				2011
	Average		Average		Average		Average
	Coupon		Days To		Coupon		Days To
	Rate (%)		Maturity		Rate (%)		Maturity
Commercial Paper		0.305		138		0.191		116
Corporate bonds and notes		2.965		112		4.921		228

The following table presents the fair value and unrealized losses related to our investments that have been in a continuous unrealized loss position for less than twelve months as of December 31,

	2012					2011
	Fair Value		Unrealized Losses			Fair Value		Unrealized Losses
	(Thousands of dollars)
Commercial Paper	$	2,494	$	(2	)	$	15,678	$	(12	)
Corporate bonds and notes		16,771		(11	)		17,226		(48	)
Total	$	19,265	$	(13	)	$	32,904	$	(60	)

The following table presents the fair value and unrealized losses related to our investments that have been in a continuous unrealized loss position for twelve months or more as of December 31,

	2012					2011
	Fair Value		Unrealized Losses			Fair Value		Unrealized Losses
	(Thousands of dollars)
Corporate bonds and notes	$	2,004	$	(.4	)	$	5,172	$	(68	)
	$	2,004	$	(.4	)	$	5,172	$	(68	)

We consider the decline in market value to be due to market conditions, and we do not plan to sell these investments prior to a recovery of cost. For these reasons, we do not consider any of our investments to be other than temporarily impaired at December 31, 2012 and 2011. The assessment of whether an investment in a debt security has suffered an other-than-temporary impairment is based on whether the Company has the intent to sell or more likely than not will be required to sell the debt security before recovery of its amortized costs. Further, if the Company does not expect to recover the entire amortized cost basis of the debt security, an other-than-temporary impairment is considered to have occurred and it is measured by the present value of cash flows expected to be collected less the amortized cost basis (credit loss). The Company did not have any other-than-temporary impairments relating to credit losses on debt securities for the year ended December 31, 2012 and 2011.