Supplemental Cash Flow Information (Details) - USD ($) $ in Millions	6 Months Ended	12 Months Ended
Jun. 30, 2019	Jun. 30, 2018	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Supplemental Cash Flow Elements [Abstract]
Interest Paid, Including Capitalized Interest, Operating and Investing Activities			$ 330	$ 314	$ 478
Income Taxes Paid, Net	$ 157	$ 149	$ 288	526	677
Non-cash financing spin-offs				$ 25
Real Estate Owned, Transfer from Real Estate Owned					$ 116

Non-cash financing activities related to spin-offs

No definition available.

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- Definition

The amount of cash paid during the current period to foreign, federal, state, and local authorities as taxes on income, net of any cash received during the current period as refunds for the overpayment of taxes.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=98513485&loc=d3e4297-108586

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- Definition

Amount of cash paid for interest, including, but not limited to, capitalized interest and payment to settle zero-coupon bond attributable to accreted interest of debt discount and debt instrument with insignificant coupon interest rate in relation to effective interest rate of borrowing attributable to accreted interest of debt discount; classified as operating and investing activities.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=98513485&loc=d3e4297-108586

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- References

No definition available.

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- Definition

Value transferred out of real estate owned (REO) in noncash transactions.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 50
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-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
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-Topic 230
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-Section 50
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-URI http://asc.fasb.org/extlink&oid=98513485&loc=d3e4313-108586

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