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

No definition available.

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The amount of debt discount that was originally recognized at the issuance of the instrument.

+ References

No definition available.

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- Definition

This amount is a multiple of the Company's aggregate investment in the Federal Home Loan Bank representing the Company's ability to borrow from the Federal Home Loan Bank.

+ References

No definition available.

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- Definition

This element represents the amount of concurrent debt outstanding which, if accelerated for any reason of default, causes an event of default on the referenced debt.

+ References

No definition available.

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- Definition

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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
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- Definition

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

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 55
-Paragraph 8
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Period Type:	instant

- Definition

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

+ References

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- Definition

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

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
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Period Type:	instant

- Definition

Interest rate of advances made and reported by Federal Home Loan Bank (FHLBank).

+ References

No definition available.

+ Details

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Data Type:	num:percentItemType
Balance Type:	na
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- Definition

Federal Home Loan Bank (FHLB) stock represents an equity interest in a FHLB. It does not have a readily determinable fair value because its ownership is restricted and it lacks a market (liquidity).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 325
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=75031641&loc=d3e63345-112809

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- Definition

Amount of current borrowing capacity under the credit facility considering any current restrictions on the amount that could be borrowed (for example, borrowings may be limited by the amount of current assets), but without considering any amounts currently outstanding under the facility.

+ References

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Balance Type:	credit
Period Type:	instant

- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

+ References

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The interest rate applicable to the portion of the carrying amount of long-term borrowings outstanding as of the balance sheet date, including current maturities, which accrues interest at a set, unchanging rate.

+ References

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- Definition

The cash inflow from additional borrowings, net of cash paid to third parties in connection with debt origination.

+ References

No definition available.

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Indebtedness (Narrative) (Details) $ in Thousands	3 Months Ended	12 Months Ended
Indebtedness (Narrative) (Details) $ in Thousands	Dec. 31, 2005 USD ($)	Dec. 31, 2016 USD ($)	Dec. 31, 2017 USD ($)	Mar. 31, 2015 USD ($)	Dec. 31, 2004 USD ($)
Net proceeds from the issuance		$ 15,000
Borrowing threshold of FHLBI			20
Federal Home Loan Bank Advances		45,000
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
Long-term Debt, Percentage Bearing Fixed Interest, Percentage Rate			5.88%
Redemption Of Seven Point Fifty Percent Junior Notes [Member]
Aggregate principal amount of notes				$ 100,000
Six Point Seventy Percent Senior Notes due 2035 [Member]
Aggregate principal amount of notes	$ 100,000
Discount for notes issued	$ 700
Effective yield	6.754%
Acceleration of principal			$ 10,000
Net proceeds from the issuance	$ 50,000
Long-term Debt, Gross			$ 100,000
Long-term Debt, Percentage Bearing Fixed Interest, Percentage Rate			6.70%
Seven Point Twenty Five Percent Senior Notes due 2034 [Member]
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
Acceleration of principal			$ 10,000
Long-term Debt, Gross			$ 50,000
Long-term Debt, Percentage Bearing Fixed Interest, Percentage Rate			7.25%
Line of Credit expires Dec.1, 2020 [Member]
Acceleration of principal			$ 20,000
Line of credit borrowing capacity			30,000
Line of credit, maximum borrowing capacity			50,000
One Point Sixty One Percent Borrowing From Federal Home Loan Bank Due July 21, 2021 [Member]
Long-term Debt, Gross			$ 25,000
Long-term Debt, Percentage Bearing Fixed Interest, Percentage 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
Long-term Debt, Percentage Bearing Fixed Interest, Percentage Rate			1.56%
Zero Point Seventy Five Percent Borrowing From Federal Home Loan Bank Due March 21, 2017 [Member]
Federal Home Loan Bank Advances			$ 64,000
Federal Home Loan Bank, Advances, Interest Rate			0.75%
One Point Two Nine Percent Borrowing From Federal Home Loan Bank Due November 15, 2017 [Member]
Federal Home Loan Bank Advances			$ 20,000
Federal Home Loan Bank, Advances, Interest Rate			1.29%
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		$ 2,800	$ 2,600