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Indebtedness (Narrative) (Details) $ in Thousands	3 Months Ended	12 Months Ended
	Dec. 31, 2005 USD ($)	Dec. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)	Mar. 31, 2016 USD ($)	Mar. 31, 2013 USD ($)	Dec. 31, 2004 USD ($)
Federal Home Loan Bank Advances			$ 45,000
Maximum borrowing percentage		10.00%
Borrowing threshold of FHLBI		20
Net proceeds from the issuance			15,000
Five Point Eight Hundred Seventy Five Percent Senior Notes Due 2043 [Member]
Aggregate principal amount of notes				$ 185,000
Bond proceeds to Insurance Subsidiaries as capital				$ 57,100
Long-term Debt, Gross		$ 185,000
Interest Rate		5.875%
Redemption Of Seven Point Fifty Percent Junior Notes [Member]
Aggregate principal amount of notes					$ 100,000
Interest Rate					7.50%
Six Point Seventy Percent Senior Notes due 2035 [Member]
Acceleration of principal		$ 10,000
Aggregate principal amount of notes	$ 100,000
Discount for notes issued	$ 700
Effective yield	6.754%
Net proceeds from the issuance	$ 50,000
Long-term Debt, Gross		$ 100,000
Interest Rate		6.70%
Seven Point Twenty Five Percent Senior Notes due 2034 [Member]
Acceleration of principal		$ 10,000
Aggregate principal amount of notes						$ 50,000
Discount for notes issued						$ 100
Effective yield						7.27%
Bond proceeds to Insurance Subsidiaries as capital						$ 25,000
Long-term Debt, Gross		$ 50,000
Interest Rate		7.25%
Line of Credit expires Dec.1, 2020 [Member]
Line of credit borrowing capacity		$ 30,000
Line of credit, maximum borrowing capacity		50,000
Acceleration of principal		20,000
One Point Sixty One Percent Borrowing From Federal Home Loan Bank Due July 21, 2021 [Member]
Long-term Debt, Gross		$ 25,000
Interest Rate		1.61%
One Point Fifty Six Percent Borrowing From Federal Home Loan Bank Due August 16, 2021 [Member]
Long-term Debt, Gross		$ 25,000
Interest Rate		1.56%
One Point Seventy Five Percent Borrowing From Federal Home Loan Bank Due March 20, 2018 [Member]
Federal Home Loan Bank Advances		$ 75,000
Federal Home Loan Bank, Advances, Interest Rate		1.75%
One Point Ninety Eight Percent Borrowing From Federal Home Loan Bank Due April 18, 2018 [Member]
Federal Home Loan Bank Advances		$ 55,000
Federal Home Loan Bank, Advances, Interest Rate		1.98%
Federal Home Loan Bank of Indianapolis [Member]
Aggregate investment in FHLBI		$ 2,800
Federal Home Loan Bank of New York [Member]
Aggregate investment in FHLBI		$ 2,700	$ 2,600

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The cash inflow from the bond proceeds contributed to the Insurance Subsidiaries as capital.

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Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

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Face (par) amount of debt instrument at time of issuance.

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Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium.

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Amount of Federal Home Loan Bank (FHLBank) advances to member financial institutions.

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