Indebtedness (Narrative) (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Mar. 31, 2013	Dec. 31, 2005	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2004	Dec. 31, 2009	Jan. 31, 2015	Dec. 31, 2011
Aggregate investment in FHLBI			$ 2.9	$ 2.9
Borrowing threshold of FHLBI			20
FLHBI Borrowing			45
Maximum FHLBI borrowing percentage permitted by line of credit			10.00%
Long-term Line of Credit			0
Five Point Eight Hundred Seventy Five Percent Senior Notes Due 2043 [Member]
Aggregate principal amount of notes	185
Bond proceeds to Insurance Subsidiaries as capital	57.1
Redemption Of Seven Point Fifty Percent Junior Notes [Member]
Aggregate principal amount of notes	100
Write off of Deferred Debt Issuance Cost	3.3
Seven Point Twenty Five Percent Senior Notes due 2034 [Member]
Aggregate principal amount of notes					50
Discount for notes issued					0.1
Effective yield					7.27%
Bond proceeds to Insurance Subsidiaries as capital					25.0
Acceleration of principal			10
Six Point Seventy Percent Senior Notes due 2035 [Member]
Aggregate principal amount of notes		100
Discount for notes issued		0.7
Effective yield		6.754%
Acceleration of principal			10
Net proceeds from the issuance		50
Two Point Ninety Percent Borrowing From Federal Home Loan Bank due Dec. 15, 2014[Member]
FLHBI Borrowing						13
Unpaid principal amount interest rate						2.90%
Zero Point Sixty Three Percent Borrowing From Federal Home Loan Bank Due July 22, 2016 [Member]
FLHBI Borrowing							15
Unpaid principal amount interest rate							0.63%
One Point Twenty Five Percent Borrowing From Federal Home Loan Bank due Dec. 16, 2016 [Member]
FLHBI Borrowing								45
Unpaid principal amount interest rate								1.25%
Line of Credit expires Sept 26,2017 [Member]
Acceleration of principal			20
Line of credit borrowing capacity			30
Line of credit, maximum borrowing capacity			$ 50