Investments (Details 1) (USD $) In Thousands, unless otherwise specified	6 Months Ended		12 Months Ended
	Jun. 30, 2014 Number		Dec. 31, 2013 Number
Fixed maturity securities, Fair Value
Fixed maturity securities, Fair Value, 12 Months or Less	$ 370,998		$ 1,672,852
Fixed maturity securities, Fair Value, More than 12 Months	721,280		83,093
Fixed maturity securities, Fair Value, Total	1,092,278		1,755,945
Fixed maturity securities, Gross Unrealized Losses
Fixed maturity securities, Gross Unrealized Losses, 12 Months or Less	5,452		108,594
Fixed maturity securities, Gross Unrealized Losses, More than 12 Months	30,210		13,943
Fixed maturity securities, Gross Unrealized Losses, Total	35,662		122,537
Number of positions with a gross unrealized loss position, 12 Months or Less	115		534
Number of position with a gross unrealized loss position, more than 12 months	202		46
Number of position with a gross unrealized loss position, Total	317		580
Fair value as a percentage of total fixed maturities and equity securities fair value, 12 Months or Less	5.50%		27.40%
Fair value as a percentage of total fixed maturities and equity securities fair value, more than 12 months	10.60%		1.40%
Fair value as a percentage of total fixed maturities and equity securities fair value, Total	16.10%		28.80%
Mortgage-backed securities [Member]
Fixed maturity securities, Fair Value
Fixed maturity securities, Fair Value, 12 Months or Less	13,483		150,602
Fixed maturity securities, Fair Value, More than 12 Months	95,845		1,383
Fixed maturity securities, Fair Value, Total	109,328		151,985
Fixed maturity securities, Gross Unrealized Losses
Fixed maturity securities, Gross Unrealized Losses, 12 Months or Less	637		19,145
Fixed maturity securities, Gross Unrealized Losses, More than 12 Months	9,054		415
Fixed maturity securities, Gross Unrealized Losses, Total	9,691		19,560
Other [Member]
Fixed maturity securities, Fair Value
Fixed maturity securities, Fair Value, 12 Months or Less	5,257		249,765
Fixed maturity securities, Fair Value, More than 12 Months	165,165		4,450
Fixed maturity securities, Fair Value, Total	170,422		254,215
Fixed maturity securities, Gross Unrealized Losses
Fixed maturity securities, Gross Unrealized Losses, 12 Months or Less	26		22,479
Fixed maturity securities, Gross Unrealized Losses, More than 12 Months	7,981		872
Fixed maturity securities, Gross Unrealized Losses, Total	8,007		23,351
Municipal bonds [Member]
Fixed maturity securities, Fair Value
Fixed maturity securities, Fair Value, 12 Months or Less	45,797		375,523
Fixed maturity securities, Fair Value, More than 12 Months	151,155		42,899
Fixed maturity securities, Fair Value, Total	196,952		418,422
Fixed maturity securities, Gross Unrealized Losses
Fixed maturity securities, Gross Unrealized Losses, 12 Months or Less	2,883		26,529
Fixed maturity securities, Gross Unrealized Losses, More than 12 Months	4,632		8,086
Fixed maturity securities, Gross Unrealized Losses, Total	7,515		34,615
Foreign government bonds [Member]
Fixed maturity securities, Fair Value
Fixed maturity securities, Fair Value, 12 Months or Less	0		6,738
Fixed maturity securities, Fair Value, More than 12 Months	0		0
Fixed maturity securities, Fair Value, Total	0		6,738
Fixed maturity securities, Gross Unrealized Losses
Fixed maturity securities, Gross Unrealized Losses, 12 Months or Less	0		390
Fixed maturity securities, Gross Unrealized Losses, More than 12 Months	0		0
Fixed maturity securities, Gross Unrealized Losses, Total	0		390
Corporate bonds [Member]
Fixed maturity securities, Fair Value
Fixed maturity securities, Fair Value, 12 Months or Less	45,966		582,849
Fixed maturity securities, Fair Value, More than 12 Months	200,615		12,948
Fixed maturity securities, Fair Value, Total	246,581		595,797
Fixed maturity securities, Gross Unrealized Losses
Fixed maturity securities, Gross Unrealized Losses, 12 Months or Less	432		28,634
Fixed maturity securities, Gross Unrealized Losses, More than 12 Months	5,191		3,516
Fixed maturity securities, Gross Unrealized Losses, Total	5,623		32,150
Other mortgage-backed securities [Member]
Fixed maturity securities, Fair Value
Fixed maturity securities, Fair Value, 12 Months or Less	259,347		274,983
Fixed maturity securities, Fair Value, More than 12 Months	79,799		20,008
Fixed maturity securities, Fair Value, Total	339,146		294,991
Fixed maturity securities, Gross Unrealized Losses
Fixed maturity securities, Gross Unrealized Losses, 12 Months or Less	1,463		8,300
Fixed maturity securities, Gross Unrealized Losses, More than 12 Months	2,474		552
Fixed maturity securities, Gross Unrealized Losses, Total	3,937		8,852
Total fixed maturity securities [Member]
Fixed maturity securities, Fair Value
Fixed maturity securities, Fair Value, 12 Months or Less	369,850		1,640,460
Fixed maturity securities, Fair Value, More than 12 Months	692,579		81,688
Fixed maturity securities, Fair Value, Total	1,062,429		1,722,148
Fixed maturity securities, Gross Unrealized Losses
Fixed maturity securities, Gross Unrealized Losses, 12 Months or Less	5,441		105,477
Fixed maturity securities, Gross Unrealized Losses, More than 12 Months	29,332		13,441
Fixed maturity securities, Gross Unrealized Losses, Total	34,773		118,918
Equity securities [Member]
Fixed maturity securities, Fair Value
Fixed maturity securities, Fair Value, 12 Months or Less	1,148	[1]	32,392	[1]
Fixed maturity securities, Fair Value, More than 12 Months	28,701	[1]	1,405	[1]
Fixed maturity securities, Fair Value, Total	29,849	[1]	33,797	[1]
Fixed maturity securities, Gross Unrealized Losses
Fixed maturity securities, Gross Unrealized Losses, 12 Months or Less	11	[1]	3,117	[1]
Fixed maturity securities, Gross Unrealized Losses, More than 12 Months	878	[1]	502	[1]
Fixed maturity securities, Gross Unrealized Losses, Total	$ 889	[1]	$ 3,619	[1]

[1] Includes nonredeemable (perpetual) preferred stocks, common stocks and closed-end funds.