Investments - Narrative (Details) - USD ($) $ in Thousands	9 Months Ended
Sep. 30, 2016	Dec. 31, 2015
Schedule of Available-for-sale Securities [Line Items]
Other investments, at cost	$ 19,789	$ 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	$ 321,500	$ 334,400
Mortgage-backed securities, weighted average life	4 years

Maximum percentage of shareholders' equity security holdings held of one issuer.

No definition available.

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- Definition

Mortgage-backed securities, weighted average life

+ References

No definition available.

+ Details

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- Definition

The fair value of available-for-sale securities that serve as collateral for borrowings.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=49124121&loc=d3e5086-111524

+ Details

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- Definition

Includes other investments and securities that are not at fair value as of the balance sheet date and those that are not accounted for under the equity method.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03.1)
-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 03
-Paragraph a
-Subparagraph 1(g)
-Article 7

+ Details

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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.

+ References

No definition available.

+ Details

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