Investments	9 Months Ended
Sep. 30, 2017
Investments [Abstract]
Investments	Investments Short-term investments consist of certificates of deposits, which are stated at fair market value.

The entire disclosure for investments in certain debt and equity securities.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-URI http://asc.fasb.org/topic&trid=2196928

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 320
-URI http://asc.fasb.org/subtopic&trid=4738149

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 940
-SubTopic 320
-URI http://asc.fasb.org/subtopic&trid=2176304

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 946
-SubTopic 320
-URI http://asc.fasb.org/subtopic&trid=2324412

Reference 5: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 320
-URI http://asc.fasb.org/subtopic&trid=2209399

Reference 6: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 954
-SubTopic 320
-URI http://asc.fasb.org/subtopic&trid=2289146

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