Accounting Standards (Details) $ in Millions	9 Months Ended
Sep. 30, 2017 USD ($)
Marketing Revenues (Expense) [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Gross Billings	$ 90

Disclosure of gross transaction volume for revenues which are reported net.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section 50
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=84158767&loc=d3e18780-107790

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 605
-SubTopic 45
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=68080631&loc=d3e61052-111654

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration