Investments (Narrative) (Details) (USD $)	3 Months Ended		6 Months Ended
	Jun. 30, 2013	Jun. 30, 2012	Jun. 30, 2013	Jun. 30, 2012	Dec. 31, 2012
Net change in unrealized gains (losses) from trading account assets supporting insurance liabilities	$ 200,000	$ 200,000	$ 600,000	$ 300,000
Net investment income	105,032,000	105,322,000	207,540,000	207,179,000
Gross unrealized losses related to high or highest quality securities	131		131		9
Gross unrealized losses related to other than high or highest quality securities	6		6		6
Twelve months or more Unrealized Losses	4,621,000		4,621,000		6,895,000
Fixed Maturities [Member]
Gross unrealized losses representing declines in value of greater than 20%	1		1		6
Gross unrealized losses in a continuous loss position for less than six months	0		0		0
Equity Securities [Member]
Gross unrealized losses representing declines in value of greater than 20%	0		0		0
Gross unrealized losses in a continuous loss position for less than six months	$ 0		$ 0		$ 0
New Jersey [Member]
Commercial mortgage loan, concentration percentage	12.00%		12.00%