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Indebtedness Schedule of Long-Term Debt (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Schedule of Debt Instruments [Line Items]
Short Term Debt Gross	$ 60,000
Short-term debt	0	$ 60,000
Three Point Zero Three Percent Borrowing From Federal Home Loan Bank Due December 16, 2026 [Member]
Schedule of Debt Instruments [Line Items]
Debt Instrument, Unamortized Discount (Premium) and Debt Issuance Costs, Net	$ 0
Long-term Debt, Percentage Bearing Fixed Interest, Percentage Rate	3.03%
Long-term Debt, Gross	$ 60,000
Long-term Debt	60,000	0
One Point Fifty Six Percent Borrowing From Federal Home Loan Bank Due August 16, 2021 [Member]
Schedule of Debt Instruments [Line Items]
Debt Instrument, Unamortized Discount (Premium) and Debt Issuance Costs, Net	$ 0
Long-term Debt, Percentage Bearing Fixed Interest, Percentage Rate	1.56%
Long-term Debt, Gross	$ 25,000
Long-term Debt	25,000	0
One Point Sixty One Percent Borrowing From Federal Home Loan Bank Due July 21, 2021 [Member]
Schedule of Debt Instruments [Line Items]
Debt Instrument, Unamortized Discount (Premium) and Debt Issuance Costs, Net	$ 0
Long-term Debt, Percentage Bearing Fixed Interest, Percentage Rate	1.61%
Long-term Debt, Gross	$ 25,000
Long-term Debt	25,000	0
Five Point Eight Hundred Seventy Five [Member]
Schedule of Debt Instruments [Line Items]
Debt Instrument, Unamortized Discount (Premium) and Debt Issuance Costs, Net	$ (4,932)
Long-term Debt, Percentage Bearing Fixed Interest, Percentage Rate	5.88%
Long-term Debt, Gross	$ 185,000
Long-term Debt	180,068	179,684
Six Point Seventy Percent Senior Notes [Member]
Schedule of Debt Instruments [Line Items]
Debt Instrument, Unamortized Discount (Premium) and Debt Issuance Costs, Net	$ (1,048)
Long-term Debt, Percentage Bearing Fixed Interest, Percentage Rate	6.70%
Long-term Debt, Gross	$ 100,000
Long-term Debt	98,952	98,890
Seven Point Twenty Five Percent Senior Notes [Member]
Schedule of Debt Instruments [Line Items]
Debt Instrument, Unamortized Discount (Premium) and Debt Issuance Costs, Net	$ (353)
Long-term Debt, Percentage Bearing Fixed Interest, Percentage Rate	7.25%
Long-term Debt, Gross	$ 50,000
Long-term Debt	49,647	49,618
Long-term Debt [Member]
Schedule of Debt Instruments [Line Items]
Debt Instrument, Unamortized Discount (Premium) and Debt Issuance Costs, Net	(6,333)
Long-term Debt, Gross	445,000
Long-term Debt	$ 438,667	328,192
Zero Point Sixty Three Percent Borrowing From Federal Home Loan Bank Due July 22, 2016 [Member]
Schedule of Debt Instruments [Line Items]
Short-term Debt, Percentage Bearing Fixed Interest Rate	0.63%
Short Term Debt Gross	$ 15,000
Debt Instrument, Unamortized Discount (Premium) and Debt Issuance Costs, Net	0
Short-term debt	$ 0	15,000
One Point Twenty Five Percent Borrowing From Federal Home Loan Bank [Member]
Schedule of Debt Instruments [Line Items]
Short-term Debt, Percentage Bearing Fixed Interest Rate	1.25%
Short Term Debt Gross	$ 45,000
Debt Instrument, Unamortized Discount (Premium) and Debt Issuance Costs, Net	0
Short-term debt	0	$ 45,000
Short-term Debt [Member]
Schedule of Debt Instruments [Line Items]
Debt Instrument, Unamortized Discount (Premium) and Debt Issuance Costs, Net	$ 0

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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
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-Publisher FASB
-Name Accounting Standards Codification
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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.

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