Short- and Long-Term Investments and Investments on Deposit for Licensure (Tables)

6 Months Ended

Jun. 30, 2012

Investments, Debt and Equity Securities [Abstract]

Reconciliation schedule of available-for-sale securities from cost basis to fair value

The amortized cost, gross unrealized holding gains, gross unrealized holding losses and fair value for available-for-sale short- and long-term investments and investments on deposit for licensure held at June 30, 2012 were as follows (dollars in thousands):

	Amortized Cost		Gross Unrealized Holding Gains		Gross Unrealized Holding Losses		Fair Value
Certificates of deposit	$	13,019	$	—	$	—	$	13,019
Commercial paper	51,685		77		—		51,762
Corporate bonds	572,785		3,441		163		576,063
Debt securities of government sponsored entities	219,432		616		80		219,968
Equity index funds	60,889		3,355		394		63,850
Money market funds	60,105		—		—		60,105
Municipal bonds	379,855		16,029		591		395,293
U.S. Treasury securities	19,941		62		2		20,001
Total	$	1,377,711	$	23,580	$	1,230	$	1,400,061

The amortized cost, gross unrealized holding gains, gross unrealized holding losses and fair value for available-for-sale short- and long-term investments and investments on deposit for licensure held at December 31, 2011 were as follows (dollars in thousands):

	Amortized Cost		Gross Unrealized Holding Gains		Gross Unrealized Holding Losses		Fair Value
Certificates of deposit	$	118,081	$	13	$	—	$	118,094
Commercial paper	172,657		2		95		172,564
Corporate bonds	565,382		2,852		1,510		566,724
Debt securities of government sponsored entities	289,901		742		100		290,543
Equity index funds	40,146		1,355		658		40,843
Money market funds	15,067		—		—		15,067
Municipal bonds	394,599		16,978		1,000		410,577
U.S. Treasury securities	26,045		80		1		26,124
Total	$	1,621,878	$	22,022	$	3,364	$	1,640,536

Schedule of amortized cost and fair value of available-for-sale debt securities by contractual maturity

The amortized cost and fair value of investments in debt securities, by contractual maturity, for available-for-sale short- and long-term investments and investments on deposit for licensure held at June 30, 2012 were as follows (dollars in thousands):

	Amortized Cost		Fair Value
Maturing within one year	$	456,138	$	456,893
Maturing between one year and five years	604,792		610,121
Maturing between five years and ten years	206,261		216,985
Maturing in greater than ten years	49,631		52,212
Total	$	1,316,822	$	1,336,211

Schedule of available-for-sale securities with unrealized losses not deemed to be other-than-temporarily impaired

The following tables show the fair value of the Company’s available-for-sale investments with unrealized losses that are not deemed to be other-than-temporarily impaired at June 30, 2012 and December 31, 2011. Investments are aggregated by investment category and length of time that individual securities have been in a continuous unrealized loss position (dollars in thousands):

	Less than 12 Months					12 Months or Greater
	Fair Value		Gross Unrealized Holding Losses		Total Number of Securities	Fair Value		Gross Unrealized Holding Losses		Total Number of Securities
June 30, 2012:
Corporate bonds	$	68,680	$	123	68	$	6,861	$	40	3
Debt securities of government sponsored entities	19,719		80		11	—		—		—
Equity index funds	11,353		394		6	—		—		—
Municipal bonds	39,325		85		30	5,744		506		2
U.S. Treasury securities	14,111		2		5	—		—		—
Total temporarily impaired securities	$	153,188	$	684	120	$	12,605	$	546	5
	Less than 12 Months					12 Months or Greater
	Fair Value		Gross Unrealized Holding Losses		Total Number of Securities	Fair Value		Gross Unrealized Holding Losses		Total Number of Securities
December 31, 2011:
Commercial paper	$	149,074	$	95	12	$	—	$	—	—
Corporate bonds	185,231		1,498		98	8,989		12		1
Debt securities of government sponsored entities	103,766		100		28	—		—		—
Equity index funds	17,021		658		5	—		—		—
Municipal bonds	5,129		1		1	11,551		999		3
U.S. Treasury securities	12,025		1		3	—		—		—
Total temporarily impaired securities	$	472,246	$	2,353	147	$	20,540	$	1,011	4

Realized gains and losses from the sale or call of available-for-sale securities

Realized gains and losses for the three and six months ended June 30, 2012 and 2011 were as follows (dollars in thousands):

	Three Months Ended June 30,						Six Months Ended June 30,
	2012			2011			2012			2011
Gross realized gains	$	646		$	11		$	2,522		$	50
Gross realized losses	(51		)	(7		)	(52		)	(9		)
Net realized gains	$	595		$	4		$	2,470		$	41