Investments (Fixed Maturities Proceeds)(Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended				6 Months Ended
	Jun. 30, 2012		Jun. 30, 2011		Jun. 30, 2012		Jun. 30, 2011
Equity Securities [Member]
Fixed maturity and equity security impairments
Writedowns for impairments on equity securities	$ 0		$ 750		$ 0		$ 750
Fixed Maturities, Available For Sale [Member]
Available For Sale
Proceeds from sales	33,498		300,188		316,818		551,902
Proceeds from maturities/repayments	224,664		78,882		373,805		230,106
Gross investment gains from sales	6,894		30,240		14,032		45,964
Available-for-sale Securities, Gross Realized Losses	23		0		24		0
Fixed maturity and equity security impairments
Net writedowns for other-than-temporary impairment losses on fixed maturities recognized in earnings	$ (83)	[1]	$ (140)	[1]	$ (152)	[1]	$ (299)	[1]

[1] Excludes the portion of other-than-temporary impairments recorded in “Other comprehensive income (loss),” representing any difference between the fair value of the impaired debt security and the net present value of its projected future cash flows at the time of impairment.