Investments

3 Months Ended

Mar. 31, 2013

Investment [Abstract]

Investments

(2)  Investments

The cost or amortized cost, gross unrealized gain or loss, and fair value of our available for sale fixed maturity and equity securities were as follows:

		Cost or		Gross		Gross
		amortized		unrealized		unrealized
		cost		gain		loss		Fair value
March 31, 2013
U.S. government and government agency securities		$	122,242	$	4,007	$	0	$	126,249
Fixed maturity securities of states, municipalities and political
	subdivisions		955,228		88,266		(493)		1,043,001
Special purpose revenue bonds of states, municipalities and
	political subdivisions		2,101,195		155,078		(5,083)		2,251,190
Corporate securities			1,248,289		58,310		(4,974)		1,301,625
Residential mortgage-backed securities			630,822		26,807		(2,006)		655,623
Commercial mortgage-backed securities			488,000		35,107		(1,044)		522,063
Asset-backed securities			42,015		515		0		42,530
Foreign government securities			231,601		12,034		(460)		243,175
	Total fixed maturity securities	$	5,819,392	$	380,124	$	(14,060)	$	6,185,456
Equity securities		$	319,499	$	34,632	$	(3,779)	$	350,352

		Cost or		Gross		Gross
		amortized		unrealized		unrealized
		cost		gain		loss		Fair value
December 31, 2012
U.S. government and government agency securities		$	195,049	$	4,560	$	(2)	$	199,607
Fixed maturity securities of states, municipalities and political
	subdivisions		969,966		96,027		(182)		1,065,811
Special purpose revenue bonds of states, municipalities and
	political subdivisions		2,033,947		168,772		(2,388)		2,200,331
Corporate securities			1,247,282		69,243		(1,355)		1,315,170
Residential mortgage-backed securities			632,665		32,560		(338)		664,887
Commercial mortgage-backed securities			482,808		41,748		(267)		524,289
Asset-backed securities			32,801		474		0		33,275
Foreign government securities			261,914		16,515		(18)		278,411
	Total fixed maturity securities	$	5,856,432	$	429,899	$	(4,550)	$	6,281,781
Equity securities		$	275,827	$	13,768	$	(4,956)	$	284,639

Substantially all of our fixed maturity securities are investment grade. The following table displays the gross unrealized losses and fair value of all available for sale securities that were in a continuous unrealized loss position for the periods indicated.

			Less than 12 months				12 months or more				Total
					Unrealized				Unrealized				Unrealized
			Fair value		losses		Fair value		losses		Fair value		losses
March 31, 2013
Fixed maturity securities
	Fixed maturity securities of states,
		municipalities and political subdivisions	$	35,621	$	(493)	$	0	$	0	$	35,621	$	(493)
	Special purpose revenue bonds of states,
		municipalities and political subdivisions		264,246		(5,067)		1,970		(16)		266,216		(5,083)
	Corporate securities			211,763		(4,112)		12,495		(862)		224,258		(4,974)
	Residential mortgage-backed securities			136,267		(2,006)		0		0		136,267		(2,006)
	Commercial mortgage-backed securities			83,541		(1,044)		0		0		83,541		(1,044)
	Foreign government securities			46,250		(460)		0		0		46,250		(460)
Equity securities				59,226		(3,779)		0		0		59,226		(3,779)
		Total	$	836,914	$	(16,961)	$	14,465	$	(878)	$	851,379	$	(17,839)

			Less than 12 months				12 months or more				Total
					Unrealized				Unrealized				Unrealized
			Fair value		losses		Fair value		losses		Fair value		losses
December 31, 2012
Fixed maturity securities
	U.S. government and government agency
		securities	$	55,034	$	(2)	$	0	$	0	$	55,034	$	(2)
	Fixed maturity securities of states,
		municipalities and political subdivisions		14,162		(182)		0		0		14,162		(182)
	Special purpose revenue bonds of states,
		municipalities and political subdivisions		155,902		(2,388)		0		0		155,902		(2,388)
	Corporate securities			85,245		(1,220)		2,616		(135)		87,861		(1,355)
	Residential mortgage-backed securities			49,486		(338)		0		0		49,486		(338)
	Commercial mortgage-backed securities			26,263		(267)		0		0		26,263		(267)
	Foreign government securities			7,007		(18)		0		0		7,007		(18)
Equity securities				103,647		(4,956)		0		0		103,647		(4,956)
		Total	$	496,746	$	(9,371)	$	2,616	$	(135)	$	499,362	$	(9,506)

A security has an impairment loss when its fair value is less than its cost or amortized cost at the balance sheet date. We evaluate our securities for possible other-than-temporary impairment losses at each quarter end. Our reviews cover all impaired securities where the loss exceeds $0.5 million and the loss eitherexceeds 10% of cost or the security had been in a loss position for longer than twelve consecutive months. We recognized no other-than-temporaryimpairment losses in the first quarter of 2013 and 2012.

We do not consider the $17.8million of gross unrealized losses on fixed maturity and equity securities in our portfolio atMarch 31, 2013 to be other-than-temporary impairments because: 1) as of March 31, 2013,we have received substantially all contractual interest and principal payments on the fixed maturity securities,2) we do not intend to sell the securities, 3) it is more likely than not that we will not be required to sell the securities before recovery of their amortized cost or cost bases and 4) the unrealized loss relates to non-credit factors, such as interest rate changes and market conditions.

The amortized cost and fair value of our fixed maturity securities at March 31, 2013, by contractual maturity, are shown below. Expected maturities may differ from contractual maturities because borrowers may have the right to call or prepay obligations with or without call or prepayment penalties. The weighted-average life of our mortgage-backed and asset-backed securities was 5.9years at March 31, 2013.

		Cost or amortized cost		Fair value
Due in 1 year or less		$	251,720	$	254,696
Due after 1 year through 5 years			1,040,973		1,089,163
Due after 5 years through 10 years			1,448,715		1,567,744
Due after 10 years through 15 years			964,983		1,040,171
Due after 15 years			952,164		1,013,466
	Securities with contractual maturities		4,658,555		4,965,240
Mortgage-backed and asset-backed securities			1,160,837		1,220,216
	Total fixed maturity securities	$	5,819,392	$	6,185,456

The sources of net investment income were as follows:

		Three months ended March 31,
		2013		2012
Fixed maturity securities
Taxable		$	25,960	$	31,115
Exempt from U.S. income taxes			27,889		26,612
	Total fixed maturity securities		53,849		57,727
Equity securities			3,580		0
Short-term investments			12		62
Other investment income			(47)		467
	Total investment income		57,394		58,256
Investment expense			(1,629)		(1,246)
	Net investment income	$	55,765	$	57,010