Investments (Mortgage Loans and Real Estate) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended			9 Months Ended			12 Months Ended
	Sep. 30, 2012		Sep. 30, 2011	Sep. 30, 2012		Sep. 30, 2011	Dec. 31, 2011
Mortgage Loans on Real Estate [Line Items]
Mortgage Loans by Loans-To-Value Ratio, Amount	$ 135,776	[1]		$ 135,776	[1]		$ 157,460	[1]
Mortgage Loans by Loans-To-Value Ratio, %	100.00%	[1]		100.00%	[1]		100.00%	[1]
Allowance for Loan and Lease Losses [Roll Forward]
Balance, beginning of period				4,571		3,962	3,962
Provision				0			609
Releases				(4,571)			0
Balance, end of period	0			0			4,571
Net gain on sale of real estate investment	(2,644)		0	(2,485)		50
Other Long-term Investments [Member]
Allowance for Loan and Lease Losses [Roll Forward]
Net gain on sale of real estate investment	2,700
Less than 50% [Member]
Mortgage Loans on Real Estate [Line Items]
Mortgage Loans by Loans-To-Value Ratio, Amount	58,307	[1]		58,307	[1]		68,048	[1]
Mortgage Loans by Loans-To-Value Ratio, %	42.90%	[1]		42.90%	[1]		43.20%	[1]
50% to 60% [Member]
Mortgage Loans on Real Estate [Line Items]
Mortgage Loans by Loans-To-Value Ratio, Amount	17,719	[1]		17,719	[1]		32,091	[1]
Mortgage Loans by Loans-To-Value Ratio, %	13.10%	[1]		13.10%	[1]		20.40%	[1]
60% to 70% [Member]
Mortgage Loans on Real Estate [Line Items]
Mortgage Loans by Loans-To-Value Ratio, Amount	27,685	[1]		27,685	[1]		25,692	[1]
Mortgage Loans by Loans-To-Value Ratio, %	20.40%	[1]		20.40%	[1]		16.30%	[1]
70% to 80% [Member]
Mortgage Loans on Real Estate [Line Items]
Mortgage Loans by Loans-To-Value Ratio, Amount	8,659	[1]		8,659	[1]		5,505	[1]
Mortgage Loans by Loans-To-Value Ratio, %	6.40%	[1]		6.40%	[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]		0	[1]
Mortgage Loans by Loans-To-Value Ratio, %	0.00%	[1]		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	$ 23,406	[1]		$ 23,406	[1]		$ 26,124	[1]
Mortgage Loans by Loans-To-Value Ratio, %	17.20%	[1]		17.20%	[1]		16.60%	[1]

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