Nature of Operations and Basis of Presentation (Narratives) (Details) (USD $)	3 Months Ended		6 Months Ended
	Jun. 30, 2012	Jun. 30, 2011	Jun. 30, 2012 segments	Jun. 30, 2011
Item Effected [Line Items]
Number of business segments			2
Payment for income taxes			$ 8,900,000	$ 600,000
Federal tax refund received			15,500,000
Interest payment			800,000	400,000
Federal income tax expense (benefit)	4,461,000	(13,082,000)	10,153,000	(11,953,000)
Income Statement Impact of Updated Accounting Guidance on a Prospective Basis [Abstract]
Additional expense on pretax basis	180,469,000	212,800,000	349,292,000	349,937,000
Increase to other underwriting expenses	20,541,000	14,720,000	42,535,000	30,777,000
Decrease to amortization of deferred policy acquisition recoverability			(67,056,000)
Decrease to net income	(14,716,000)	17,914,000	(33,900,000)	12,104,000
Decrease to net income per share	$ (0.58)	$ 0.69	$ (1.33)	$ 0.46
Property and Casualty Insurance [Member]
Item Effected [Line Items]
Number of states in which we are licensed as insurer	43		43
Income Statement Impact of Updated Accounting Guidance on a Prospective Basis [Abstract]
Decrease to amortization of deferred policy acquisition recoverability			(62,621,000)
Decrease to net income	(13,355,000)	19,574,000	(29,991,000)	16,224,000
Life Insurance [Member]
Item Effected [Line Items]
Number of states in which we are licensed as insurer	36		36
Income Statement Impact of Updated Accounting Guidance on a Prospective Basis [Abstract]
Decrease to amortization of deferred policy acquisition recoverability			(4,435,000)
Decrease to net income	(1,361,000)	(1,660,000)	(3,909,000)	(4,120,000)
Accounting Standards Update 2010-26 [Member]
Income Statement Impact of Updated Accounting Guidance on a Prospective Basis [Abstract]
Additional expense on pretax basis			8,100,000
Increase to other underwriting expenses			13,900,000
Decrease to amortization of deferred policy acquisition recoverability			(5,800,000)
Decrease to net income			$ (5,300,000)
Decrease to net income per share			$ (0.21)