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Investments - Held-to-maturity Security - Narrative (Details) $ in Millions | 9 Months Ended
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Sep. 30, 2016 USD ($)
Schedule Of Held To Maturity Securities [Line Items] |
Held-to-maturity debt security estimated unrealized holding gain | $ 46.8
LLC Note [Member] |
Schedule Of Held To Maturity Securities [Line Items] |
Debt instrument, interest rate, stated percentage | 4.50%

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- Definition Contractual interest rate for funds borrowed, under the debt agreement. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.22(a)(1)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
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- Definition Amount of unrecognized gain before loss on investments in held-to-maturity securities. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 5 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=73527792&loc=d3e27232-111563 + Details
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