Investments (Mortgage Loans and Real Estate) (Details) (USD $) In Thousands, unless otherwise specified	6 Months Ended		12 Months Ended
	Jun. 30, 2012		Dec. 31, 2011
Mortgage Loans on Real Estate [Line Items]
Mortgage Loans by Loans-To-Value Ratio, Amount	$ 132,614	[1]	$ 157,460	[1]
Mortgage Loans by Loans-To-Value Ratio, %	100.00%	[1]	100.00%	[1]
Allowance for Loan and Lease Losses [Roll Forward]
Balance, beginning of period	4,571		3,962
Provision	0		609
Releases	(4,571)		0
Balance, end of period	0		4,571
Less than 50% [Member]
Mortgage Loans on Real Estate [Line Items]
Mortgage Loans by Loans-To-Value Ratio, Amount	62,711	[1]	68,048	[1]
Mortgage Loans by Loans-To-Value Ratio, %	47.30%	[1]	43.20%	[1]
50% to 60% [Member]
Mortgage Loans on Real Estate [Line Items]
Mortgage Loans by Loans-To-Value Ratio, Amount	15,617	[1]	32,091	[1]
Mortgage Loans by Loans-To-Value Ratio, %	11.80%	[1]	20.40%	[1]
60% to 70% [Member]
Mortgage Loans on Real Estate [Line Items]
Mortgage Loans by Loans-To-Value Ratio, Amount	25,787	[1]	25,692	[1]
Mortgage Loans by Loans-To-Value Ratio, %	19.40%	[1]	16.30%	[1]
70% to 80% [Member]
Mortgage Loans on Real Estate [Line Items]
Mortgage Loans by Loans-To-Value Ratio, Amount	4,978	[1]	5,505	[1]
Mortgage Loans by Loans-To-Value Ratio, %	3.80%	[1]	3.50%	[1]
80% to 90% [Member]
Mortgage Loans on Real Estate [Line Items]
Mortgage Loans by Loans-To-Value Ratio, Amount	0	[1]	0	[1]
Mortgage Loans by Loans-To-Value Ratio, %	0.00%	[1]	0.00%	[1]
Greater than 90% [Member]
Mortgage Loans on Real Estate [Line Items]
Mortgage Loans by Loans-To-Value Ratio, Amount	$ 23,521	[1]	$ 26,124	[1]
Mortgage Loans by Loans-To-Value Ratio, %	17.70%	[1]	16.60%	[1]

[1] Loan-to-Value Ratio using the most recent appraised value.