Fair Value Measurements

6 Months Ended

Jun. 30, 2011

Fair Value Measurements [Abstract]

Fair Value Measurements

5. Fair Value Measurements

Our consolidated balance sheets include the following financial instruments: cash and cash equivalents, investments, receivables, trade accounts payable, medical claims and benefits payable, long-term debt, and other liabilities. We consider the carrying amounts of cash and cash equivalents, receivables, other current assets and current liabilities to approximate their fair value because of the relatively short period of time between the origination of these instruments and their expected realization or payment. For a comprehensive discussion of fair value measurements with regard to our current and non-current investments, see below.

The carrying amount of the convertible senior notes was $166.7 million and $164.0 million as of June 30, 2011, and December 31, 2010, respectively. Based on quoted market prices, the fair value of the convertible senior notes was approximately $215.8 million and $188.4 million as of June 30, 2011, and December 31, 2010, respectively.

To prioritize the inputs we use in measuring fair value, we apply a three-tier fair value hierarchy. These tiers include: Level 1, defined as observable inputs such as quoted prices in active markets; Level 2, defined as inputs other than quoted prices in active markets that are either directly or indirectly observable; and Level 3, defined as unobservable inputs in which little or no market data exists, therefore requiring an entity to develop its own assumptions.

As of June 30, 2011, we held certain assets that are required to be measured at fair value on a recurring basis. These included current investments in investment-grade debt securities that are designated as available-for-sale, and are reported at fair value based on market prices that are readily available (Level 1). See Note 6, “Investments,” for further information regarding fair value.

We also held investments in auction rate securities which are designated as available-for-sale, and are reported at fair value of $19.0 million (par value of $22.4 million) as of June 30, 2011.

Our investments in auction rate securities are collateralized by student loan portfolios guaranteed by the U.S. government. We continued to earn interest on substantially all of these auction rate securities as of June 30, 2011. Due to events in the credit markets, the auction rate securities held by us experienced failed auctions beginning in the first quarter of 2008. As such, quoted prices in active markets were not readily available during the majority of 2008, 2009, and 2010, and continued to be unavailable as of June 30, 2011. To estimate the fair value of these securities, we used pricing models that included factors such as the collateral underlying the securities, the creditworthiness of the counterparty, the timing of expected future cash flows, and the expectation of the next time the security would have a successful auction. The estimated values of these securities were also compared, when possible, to valuation data with respect to similar securities held by other parties. We concluded that these estimates, given the lack of market available pricing, provided a reasonable basis for determining the fair value of the auction rate securities as of June 30, 2011. For our investments in auction rate securities, we do not intend to sell, nor is it more likely than not that we will be required to sell, these investments before recovery of their cost.

As a result of changes in the fair value of auction rate securities designated as available-for-sale, we recorded pretax unrealized gains of $0.7 million and pretax unrealized losses of $0.2 million to accumulated other comprehensive income (loss) for the six months ended June 30, 2011, and 2010, respectively. Any future fluctuation in fair value related to these instruments that we deem to be temporary, including any recoveries of previous write-downs, would be recorded to accumulated other comprehensive income (loss). If we determine that any future valuation adjustment was other-than-temporary, we would record a charge to earnings as appropriate.

Until July 2, 2010, we held certain auction rate securities (designated as trading securities) with an investment securities firm. In 2008, we entered into a rights agreement with this firm that (1) allowed us to exercise rights (the “Rights”) to sell the eligible auction rate securities at par value to this firm between June 30, 2010 and July 2, 2012, and (2) gave the investment securities firm the right to purchase the auction rate securities from us any time after the agreement date as long as we received the par value. On June 30, 2010, and July 1, 2010, all of the eligible auction rate securities remaining at that time were settled at par value. During 2010, the aggregate auction rate securities (designated as trading securities) settled amounted to $40.9 million par value (fair value $36.7 million). Substantially all of the difference between par value and fair value on these securities was recovered through the rights agreement. For the six months ended 2010, we recorded pretax gains of $2.9 million on the auction rate securities underlying the Rights.

We accounted for the Rights as a freestanding financial instrument and, until July 2, 2010, recorded the value of the Rights under the fair value option. For the six months ended 2010, we recorded pretax losses of $2.6 million on the Rights, attributable to the decline in the fair value of the Rights. When the remaining eligible auction rate securities were sold at par value on July 1, 2010, the value of the Rights was zero.

Our assets measured at fair value on a recurring basis at June 30, 2011, were as follows:

	Total		Level 1		Level 2		Level 3
	(In thousands)
Corporate debt securities	$	243,277	$	243,277	$	—	$	—
Government-sponsored enterprise securities (GSEs)		36,797		36,797		—		—
Municipal securities		41,028		41,028		—		—
U.S. treasury notes		32,240		32,240		—		—
Certificates of deposit		3,258		3,258		—		—
Auction rate securities		18,958		—		—		18,958
	$	375,558	$	356,600	$	—	$	18,958

The following table presents our assets measured at fair value on a recurring basis using significant unobservable inputs (Level 3):

	(Level 3)
	(In thousands)
Balance at December 31, 2010	$	20,449
Total gains (realized or unrealized):
Included in other comprehensive income		659
Settlements		(2,150	)
Balance at June 30, 2011	$	18,958
The amount of total gains for the period included in other comprehensive income attributable to the change in unrealized gains relating to assets still held at June 30, 2011	$	659

In 2010, we recorded a $2.8 million liability for contingent consideration related to the acquisition of our Wisconsin health plan. In the first quarter of 2011, we determined that there was no liability for contingent consideration relating to the acquisition. The liability for contingent consideration related to this acquisition was measured at fair value on a recurring basis using significant unobservable inputs (Level 3). The following table presents a roll forward of this liability for 2011:

	(Level 3)
	(In thousands)
Balance at December 31, 2010	$	(2,800	)
Total gains included in earnings		2,800
Balance at June 30, 2011	$	—