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v3.3.1.900

Fair Value Measurements (Carrying Value and Estimated Fair Value of Financial Instruments) (Details) - USD ($) $ in Thousands | Dec. 31, 2015 | Dec. 31, 2014
--- | --- | ---
Held-to-maturity Securities | $ 201,354 | $ 318,137
Available-for-sale Securities, Debt Securities | 4,408,203 | 4,066,122
Equity securities, AFS | 207,051 | 191,400
Short-term investments | 194,819 | 131,972
Notes payable | 388,192 | 372,689
Carrying Amount [Member] |  |
Held-to-maturity Securities | 201,354 | 318,137
Available-for-sale Securities, Debt Securities | 4,408,203 | 4,066,122
Equity securities, AFS | 207,051 | 191,400
Short-term investments | 194,819 | 131,972
Notes payable | 388,192 | 372,689
Carrying Amount [Member] | Zero Point Sixty Three Percent Borrowing From Federal Home Loan Bank Due July 22, 2016 [Member] |  |
Notes payable | 15,000 | 0
Carrying Amount [Member] | One Point Twenty Five Percent Borrowing From Federal Home Loan Bank [Member] |  |
Notes payable | 45,000 | 45,000
Carrying Amount [Member] | Seven Point Twenty Five Percent Senior Notes [Member] |  |
Notes payable | 49,898 | 49,896
Carrying Amount [Member] | Six Point Seventy Percent Senior Notes [Member] |  |
Notes payable | 99,415 | 99,401
Carrying Amount [Member] | Five Point Eight Hundred Seventy Five [Member] |  |
Notes payable | 185,000 | 185,000
Carrying Amount [Member] | Long Term Debt Excluding Issuance Costs [Member] |  |
Notes payable | 394,313 | 379,297
Carrying Amount [Member] | Unamortized Debt Issuance Costs [Member] |  |
Notes payable | (6,121) | (6,608)
Fair Value [Member] |  |
Held-to-maturity Securities | 209,544 | 333,961
Available-for-sale Securities, Debt Securities | 4,408,203 | 4,066,122
Equity securities, AFS | 207,051 | 191,400
Short-term investments | 194,819 | 131,972
Notes payable | 419,826 | 404,270
Fair Value [Member] | Zero Point Sixty Three Percent Borrowing From Federal Home Loan Bank Due July 22, 2016 [Member] |  |
Notes payable | 14,977 | 0
Fair Value [Member] | One Point Twenty Five Percent Borrowing From Federal Home Loan Bank [Member] |  |
Notes payable | 45,083 | 45,244
Fair Value [Member] | Seven Point Twenty Five Percent Senior Notes [Member] |  |
Notes payable | 56,929 | 59,181
Fair Value [Member] | Six Point Seventy Percent Senior Notes [Member] |  |
Notes payable | 110,363 | 114,845
Fair Value [Member] | Five Point Eight Hundred Seventy Five [Member] |  |
Notes payable | $ 192,474 | $ 185,000

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