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Investment Portfolio - Narrative (Detail) $ in Millions	Jun. 30, 2015 USD ($)
Investments, Debt and Equity Securities [Abstract]
fair value of investment	$ 53.4
Cost basis of portfolio investments	$ 45.4

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- Definition

Cost basis of portfolio investments.

+ References

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- Definition

Fair value portion of investment securities, including, but not limited to, marketable securities, derivative financial instruments, and investments accounted for under the equity method.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef



-Publisher FASB



-Name Accounting Standards Codification



-Glossary Trading Securities



-URI http://asc.fasb.org/extlink&oid=6526789



Reference 2: http://www.xbrl.org/2003/role/presentationRef



-Publisher FASB



-Name Accounting Standards Codification



-Topic 320



-SubTopic 10



-Section 35



-Paragraph 1



-URI http://asc.fasb.org/extlink&oid=27723805&loc=d3e24584-111560



Reference 3: http://www.xbrl.org/2003/role/presentationRef



-Publisher FASB



-Name Accounting Standards Codification



-Topic 320



-SubTopic 10



-Section 25



-Paragraph 1



-URI http://asc.fasb.org/extlink&oid=51813488&loc=d3e22054-111558



Reference 4: http://www.xbrl.org/2003/role/presentationRef



-Publisher FASB



-Name Accounting Standards Codification



-Glossary Available-for-Sale Securities



-URI http://asc.fasb.org/extlink&oid=6505594



Reference 5: http://www.xbrl.org/2003/role/presentationRef



-Publisher SEC



-Name Regulation S-X (SX)



-Number 210



-Section 03



-Paragraph 1



-Subparagraph a, f, g



-Article 7

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