Investments (Details 4) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2014		Dec. 31, 2013
Cumulative credit loss (1)
Beginning of period	$ 4,097	[1]	$ 2,877	[1]
New credit losses	280	[1]	1,220	[1]
Losses related to securities sold or paid down during the period	(1,500)	[1]	0	[1]
End of period	$ 2,877	[1]	$ 4,097	[1]

[1] The cumulative credit loss amounts exclude other-than-temporary impairment losses on securities held as of the periods indicated that the Company intended to sell or it was more likely than not that the Company would be required to sell the security before the recovery of the amortized cost basis.