v3.3.1.900

Investments - Narrative (Details) - USD ($) $ in Thousands | 12 Months Ended |
--- | --- | ---
Dec. 31, 2014 | Dec. 31, 2015
Schedule of Available-for-sale Securities [Line Items] |  |
Other investments, at cost | $ 17,037 | $ 17,455
Maximum percentage of shareholders' equity security holdings held of one issuer | 10.00% | 10.00%
Available-for-sale securities pledged as collateral, fair value | $ 315,800 | $ 334,400
Available for sale securities transferred to held to maturity |  | 46,600
Mortgage-backed securities, weighted average life | 4 years |
Des Moines |  |
Schedule of Available-for-sale Securities [Line Items] |  |
Other investments, at cost |  | $ 8,300

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