Subsequent Events Subsequent Events (Details) - HFOTCO LLC [Member] - Subsequent Event [Member] $ / shares in Units, shares in Millions, $ in Millions	Jul. 17, 2017 USD ($) $ / shares shares
Subsequent Event [Line Items]
Payments to Acquire Businesses, Gross	$ 301
Business Acquisition, Equity Interest Issued or Issuable, Number of Shares \| shares	12.4
Business Acquisition, Equity Interest Issued or Issuable, Value Assigned	$ 330
Business Acquisition, Share Price \| $ / shares	$ 26.68
Secured Debt [Member]
Subsequent Event [Line Items]
Business Combination, Consideration Transferred, Liabilities Incurred	$ 761
Second Payment [Member] \| Notes Payable, Other Payables [Member]
Subsequent Event [Line Items]
Business Combination, Consideration Transferred, Liabilities Incurred	$ 600
Debt prepayment discount rate, annual rate	5.00%
Total payable if not redeemed by first due date	$ 680

Debt prepayment discount rate, annual rate

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- Definition

Total payable if not redeemed by first due date

+ References

No definition available.

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- Definition

Value of equity interests (such as common shares, preferred shares, or partnership interest) issued or issuable to acquire the entity.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 50
-Paragraph 1
-Subparagraph (b)(4)
-URI http://asc.fasb.org/extlink&oid=35744584&loc=d3e6927-128479

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- Definition

Number of shares of equity interests issued or issuable to acquire entity.

+ References

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- Definition

Price of a single share of a number of saleable stocks paid or offered to be paid in a business combination.

+ References

No definition available.

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- Definition

Amount of liabilities incurred by the acquirer as part of consideration transferred in a business combination.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 25
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=6911189&loc=d3e6405-128476

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 30
-Paragraph 7
-URI http://asc.fasb.org/extlink&oid=6911251&loc=d3e6578-128477

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 30
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=6911251&loc=d3e6613-128477

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- Definition

The cash outflow associated with the acquisition of business during the period. The cash portion only of the acquisition price.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Investing Activities
-URI http://asc.fasb.org/extlink&oid=6516133

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

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- Definition

Detail information of subsequent event by type. User is expected to use existing line items from elsewhere in the taxonomy as the primary line items for this disclosure, which is further associated with dimension and member elements pertaining to a subsequent event.

+ References

No definition available.

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