Recently Issued Accounting Pronouncements (Details) - USD ($) $ in Millions	9 Months Ended
Sep. 30, 2017	Sep. 30, 2016
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Movement in restricted cash related to acquisition	$ 0	$ (3,561)
Pro Forma \| Adjustments For ASU 2016-15 \| New Accounting Pronouncement, Early Adoption, Effect
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Movement in restricted cash related to acquisition		$ (3,600)

The net cash inflow or outflow for the increase (decrease) associated with funds that are not available for withdrawal or use (such as funds held in escrow) and are associated with underlying transactions that are classified as investing activities.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 12
-URI http://asc.fasb.org/extlink&oid=66902209&loc=d3e3179-108585

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 13
-URI http://asc.fasb.org/extlink&oid=66902209&loc=d3e3213-108585

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Investing Activities
-URI http://asc.fasb.org/extlink&oid=6516133

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