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Fair Value Measurement (Methodologies Other Than Fair Value) (Details) - USD ($) $ in Thousands | Mar. 31, 2017 | Dec. 31, 2016
--- | --- | ---
Financial assets: |  |
BOLI | $ 60,589 | $ 60,134
Other investments | 80,576 | 81,892
Other assets | 101,589 | 96,004
Financial liabilities: |  |
Debt | 448,288 | 448,202
Total other liabilities | 170,317 | 422,285
Not Measured At Fair Value [Member] | Carrying Value [Member] |  |
Financial assets: |  |
BOLI | 60,589 | 60,134
Other investments | 50,598 | 50,391
Other assets | 29,196 | 29,111
Financial liabilities: |  |
Total other liabilities | 17,855 | 17,033
Not Measured At Fair Value [Member] | Carrying Value [Member] | Senior notes due 2023 [Member] |  |
Financial liabilities: |  |
Debt | 250,000 | 250,000
Not Measured At Fair Value [Member] | Carrying Value [Member] | Revolving Credit Facility [Member] |  |
Financial liabilities: |  |
Debt | 200,000 | 200,000
Not Measured At Fair Value [Member] | Level 3 [Member] | Fair Value [Member] |  |
Financial assets: |  |
BOLI | 60,589 | 60,134
Other investments | 62,061 | 58,757
Other assets | 29,072 | 28,960
Financial liabilities: |  |
Total other liabilities | 17,855 | 17,011
Not Measured At Fair Value [Member] | Level 3 [Member] | Fair Value [Member] | Senior notes due 2023 [Member] |  |
Financial liabilities: |  |
Debt | 274,315 | 270,898
Not Measured At Fair Value [Member] | Level 3 [Member] | Fair Value [Member] | Revolving Credit Facility [Member] |  |
Financial liabilities: |  |
Debt | $ 200,000 | $ 200,000

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