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Fair Value Measurements (Quantitative Information of Our Financial Assets and Liabilities That Were Disclosed at Fair Value) (Details) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Held-to-maturity Securities	$ 201,354	$ 318,137
Notes payable	388,192	372,689
Fair Value [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Held-to-maturity Securities	209,544	333,961
Notes payable	419,826	404,270
Quoted Prices in Active Markets for Identical Assets/Liabilities (Level 1) [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Held-to-maturity Securities	0	0
Notes payable	192,474	185,000
Significant Other Observable Inputs (Level 2) [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Held-to-maturity Securities	206,208	333,961
Notes payable	227,352	219,270
Significant Unobservable Inputs (Level 3) [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Held-to-maturity Securities	3,336	0
Notes payable	0	0
Foreign Government [Member] | Fair Value [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Held-to-maturity Securities		5,394
Foreign Government [Member] | Quoted Prices in Active Markets for Identical Assets/Liabilities (Level 1) [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Held-to-maturity Securities		0
Foreign Government [Member] | Significant Other Observable Inputs (Level 2) [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Held-to-maturity Securities		5,394
Foreign Government [Member] | Significant Unobservable Inputs (Level 3) [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Held-to-maturity Securities		0
Obligations of States and Political Subdivisions [Member] | Fair Value [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Held-to-maturity Securities	181,880	299,132
Obligations of States and Political Subdivisions [Member] | Quoted Prices in Active Markets for Identical Assets/Liabilities (Level 1) [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Held-to-maturity Securities	0	0
Obligations of States and Political Subdivisions [Member] | Significant Other Observable Inputs (Level 2) [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Held-to-maturity Securities	181,880	299,132
Obligations of States and Political Subdivisions [Member] | Significant Unobservable Inputs (Level 3) [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Held-to-maturity Securities	0	0
Corporate Securities [Member] | Fair Value [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Held-to-maturity Securities	22,015	21,422
Corporate Securities [Member] | Quoted Prices in Active Markets for Identical Assets/Liabilities (Level 1) [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Held-to-maturity Securities	0	0
Corporate Securities [Member] | Significant Other Observable Inputs (Level 2) [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Held-to-maturity Securities	18,679	21,422
Corporate Securities [Member] | Significant Unobservable Inputs (Level 3) [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Held-to-maturity Securities	3,336	0
Asset-backed Securities [Member] | Fair Value [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Held-to-maturity Securities	1,028	2,823
Asset-backed Securities [Member] | Quoted Prices in Active Markets for Identical Assets/Liabilities (Level 1) [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Held-to-maturity Securities	0	0
Asset-backed Securities [Member] | Significant Other Observable Inputs (Level 2) [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Held-to-maturity Securities	1,028	2,823
Asset-backed Securities [Member] | Significant Unobservable Inputs (Level 3) [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Held-to-maturity Securities	0	0
Commercial Mortgage-backed Securities (CMBS) [Member] | Fair Value [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Held-to-maturity Securities	4,621	5,190
Commercial Mortgage-backed Securities (CMBS) [Member] | Quoted Prices in Active Markets for Identical Assets/Liabilities (Level 1) [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Held-to-maturity Securities	0	0
Commercial Mortgage-backed Securities (CMBS) [Member] | Significant Other Observable Inputs (Level 2) [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Held-to-maturity Securities	4,621	5,190
Commercial Mortgage-backed Securities (CMBS) [Member] | Significant Unobservable Inputs (Level 3) [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Held-to-maturity Securities	0	0
Zero Point Sixty Three Percent Borrowing From Federal Home Loan Bank Due July 22, 2016 [Member] | Fair Value [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Notes payable	14,977
Zero Point Sixty Three Percent Borrowing From Federal Home Loan Bank Due July 22, 2016 [Member] | Quoted Prices in Active Markets for Identical Assets/Liabilities (Level 1) [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Notes payable	0
Zero Point Sixty Three Percent Borrowing From Federal Home Loan Bank Due July 22, 2016 [Member] | Significant Other Observable Inputs (Level 2) [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Notes payable	14,977
Zero Point Sixty Three Percent Borrowing From Federal Home Loan Bank Due July 22, 2016 [Member] | Significant Unobservable Inputs (Level 3) [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Notes payable	0
One Point Twenty Five Percent Borrowing From Federal Home Loan Bank [Member] | Fair Value [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Notes payable	45,083	45,244
One Point Twenty Five Percent Borrowing From Federal Home Loan Bank [Member] | Quoted Prices in Active Markets for Identical Assets/Liabilities (Level 1) [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Notes payable	0	0
One Point Twenty Five Percent Borrowing From Federal Home Loan Bank [Member] | Significant Other Observable Inputs (Level 2) [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Notes payable	45,083	45,244
One Point Twenty Five Percent Borrowing From Federal Home Loan Bank [Member] | Significant Unobservable Inputs (Level 3) [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Notes payable	0	0
Seven Point Twenty Five Percent Senior Notes [Member] | Fair Value [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Notes payable	56,929	59,181
Seven Point Twenty Five Percent Senior Notes [Member] | Quoted Prices in Active Markets for Identical Assets/Liabilities (Level 1) [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Notes payable	0	0
Seven Point Twenty Five Percent Senior Notes [Member] | Significant Other Observable Inputs (Level 2) [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Notes payable	56,929	59,181
Seven Point Twenty Five Percent Senior Notes [Member] | Significant Unobservable Inputs (Level 3) [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Notes payable	0	0
Six Point Seventy Percent Senior Notes [Member] | Fair Value [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Notes payable	110,363	114,845
Six Point Seventy Percent Senior Notes [Member] | Quoted Prices in Active Markets for Identical Assets/Liabilities (Level 1) [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Notes payable	0	0
Six Point Seventy Percent Senior Notes [Member] | Significant Other Observable Inputs (Level 2) [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Notes payable	110,363	114,845
Six Point Seventy Percent Senior Notes [Member] | Significant Unobservable Inputs (Level 3) [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Notes payable	0	0
Five Point Eight Hundred Seventy Five [Member] | Fair Value [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Notes payable	192,474	185,000
Five Point Eight Hundred Seventy Five [Member] | Quoted Prices in Active Markets for Identical Assets/Liabilities (Level 1) [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Notes payable	192,474	185,000
Five Point Eight Hundred Seventy Five [Member] | Significant Other Observable Inputs (Level 2) [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Notes payable	0	0
Five Point Eight Hundred Seventy Five [Member] | Significant Unobservable Inputs (Level 3) [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Notes payable	$ 0	$ 0

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Amount after other than temporary impairment (OTTI) accretion, of investments in debt securities classified as held-to-maturity.

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Carrying amount of long-term debt, net of unamortized discount or premium, including current and noncurrent amounts. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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