Investments (Details 3) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2013 Number		Dec. 31, 2012 Number
Fixed maturity securities Fair Value
Fixed maturity securities, Fair Value 12 Months or Less	$ 1,672,852		$ 263,571
Fixed maturity securities, Fair Value More than 12 Months	83,093		55,788
Fixed maturity securities, Fair Value, Total	1,755,945		319,359
Fixed maturity securities Gross Unrealized Losses
Fixed maturity securities, Gross Unrealized Losses 12 Months or Less	108,594		5,648
Fixed maturity securities, Gross Unrealized Losses More than 12 Months	13,943		5,532
Fixed maturity securities, Gross Unrealized Losses, Total	122,537		11,180
Number of positions with a gross unrealized loss 12 months or less	534		156
Number of position with gross unrealized loss position more than 12 months	46		43
Number of position with gross unrealized loss position Total	580		199
Fair value as percentage of fixed maturities and equity securities fair value less than 12 months	27.40%		4.40%
Fair value as percentage of fixed maturities and equity securities fair value more than 12 months	1.40%		0.90%
Fair value as percentage of fixed maturities and equity securities fair value, Total	28.80%		5.30%
Mortgage-backed securities [Member]
Fixed maturity securities Fair Value
Fixed maturity securities, Fair Value 12 Months or Less	150,602		11,006
Fixed maturity securities, Fair Value More than 12 Months	1,383		50
Fixed maturity securities, Fair Value, Total	151,985		11,056
Fixed maturity securities Gross Unrealized Losses
Fixed maturity securities, Gross Unrealized Losses 12 Months or Less	19,145		124
Fixed maturity securities, Gross Unrealized Losses More than 12 Months	415		1
Fixed maturity securities, Gross Unrealized Losses, Total	19,560		125
Other [Member]
Fixed maturity securities Fair Value
Fixed maturity securities, Fair Value 12 Months or Less	249,765		9,944
Fixed maturity securities, Fair Value More than 12 Months	4,450		0
Fixed maturity securities, Fair Value, Total	254,215		9,944
Fixed maturity securities Gross Unrealized Losses
Fixed maturity securities, Gross Unrealized Losses 12 Months or Less	22,479		135
Fixed maturity securities, Gross Unrealized Losses More than 12 Months	872		0
Fixed maturity securities, Gross Unrealized Losses, Total	23,351		135
Municipal Bonds [Member]
Fixed maturity securities Fair Value
Fixed maturity securities, Fair Value 12 Months or Less	375,523		108,578
Fixed maturity securities, Fair Value More than 12 Months	42,899		3,990
Fixed maturity securities, Fair Value, Total	418,422		112,568
Fixed maturity securities Gross Unrealized Losses
Fixed maturity securities, Gross Unrealized Losses 12 Months or Less	26,529		2,605
Fixed maturity securities, Gross Unrealized Losses More than 12 Months	8,086		43
Fixed maturity securities, Gross Unrealized Losses, Total	34,615		2,648
Foreign government bonds [Member]
Fixed maturity securities Fair Value
Fixed maturity securities, Fair Value 12 Months or Less	6,738		0
Fixed maturity securities, Fair Value More than 12 Months	0		0
Fixed maturity securities, Fair Value, Total	6,738		0
Fixed maturity securities Gross Unrealized Losses
Fixed maturity securities, Gross Unrealized Losses 12 Months or Less	390		0
Fixed maturity securities, Gross Unrealized Losses More than 12 Months	0		0
Fixed maturity securities, Gross Unrealized Losses, Total	390		0
Corporate Bonds [Member]
Fixed maturity securities Fair Value
Fixed maturity securities, Fair Value 12 Months or Less	582,849		56,481
Fixed maturity securities, Fair Value More than 12 Months	12,948		26,725
Fixed maturity securities, Fair Value, Total	595,797		83,206
Fixed maturity securities Gross Unrealized Losses
Fixed maturity securities, Gross Unrealized Losses 12 Months or Less	28,634		875
Fixed maturity securities, Gross Unrealized Losses More than 12 Months	3,516		4,075
Fixed maturity securities, Gross Unrealized Losses, Total	32,150		4,950
Other Mortgage-backed Securities [Member]
Fixed maturity securities Fair Value
Fixed maturity securities, Fair Value 12 Months or Less	274,983		58,218
Fixed maturity securities, Fair Value More than 12 Months	20,008		25,014
Fixed maturity securities, Fair Value, Total	294,991		83,232
Fixed maturity securities Gross Unrealized Losses
Fixed maturity securities, Gross Unrealized Losses 12 Months or Less	8,300		621
Fixed maturity securities, Gross Unrealized Losses More than 12 Months	552		1,411
Fixed maturity securities, Gross Unrealized Losses, Total	8,852		2,032
Total Fixed Maturities Securities [Member]
Fixed maturity securities Fair Value
Fixed maturity securities, Fair Value 12 Months or Less	1,640,460		244,227
Fixed maturity securities, Fair Value More than 12 Months	81,688		55,779
Fixed maturity securities, Fair Value, Total	1,722,148		300,006
Fixed maturity securities Gross Unrealized Losses
Fixed maturity securities, Gross Unrealized Losses 12 Months or Less	105,477		4,360
Fixed maturity securities, Gross Unrealized Losses More than 12 Months	13,441		5,530
Fixed maturity securities, Gross Unrealized Losses, Total	118,918		9,890
Equity Securities [Member]
Fixed maturity securities Fair Value
Fixed maturity securities, Fair Value 12 Months or Less	32,392	[1]	19,344	[1]
Fixed maturity securities, Fair Value More than 12 Months	1,405	[1]	9	[1]
Fixed maturity securities, Fair Value, Total	33,797	[1]	19,353	[1]
Fixed maturity securities Gross Unrealized Losses
Fixed maturity securities, Gross Unrealized Losses 12 Months or Less	3,117	[1]	1,288	[1]
Fixed maturity securities, Gross Unrealized Losses More than 12 Months	502	[1]	2	[1]
Fixed maturity securities, Gross Unrealized Losses, Total	$ 3,619	[1]	$ 1,290	[1]

[1] Includes nonredeemable (perpetual) preferred stocks and common stocks.