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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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