Investments in Securities (Details) - Common Stock - USD ($) $ in Millions |
12 Months Ended | ||
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Dec. 31, 2016 |
Dec. 31, 2015 |
Dec. 31, 2014 |
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| Schedule of Available-for-sale Securities [Line Items] | |||
| Proceeds from (payments for) trading securities | $ 16.5 | $ 3.3 | $ 0.6 |
| Gain on sale of available-for-sale securities | $ 0.1 | ||
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- Definition Amount of cash inflow (outflow) from sales and purchases of trading securities. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. No definition available.
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- Definition This item represents the gain realized during the period from the sale of trading securities. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Details
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