Current Accounting Developments - New Accounting Pronouncements (Details)	Sep. 30, 2019
Accounting Standards Update 2016-02 [Member]
New Accounting Pronouncements or Change in Accounting Principle
Change in Accounting Principle, Accounting Standards Update, Adopted	true
Change in Accounting Principle, Accounting Standards Update, Adoption Date	Jan. 01, 2019
Change in Accounting Principle, Accounting Standards Update, Early Adoption	false
Accounting Standards Update 2016-13 [Member]
New Accounting Pronouncements or Change in Accounting Principle
Change in Accounting Principle, Accounting Standards Update, Adopted	false
Change in Accounting Principle, Accounting Standards Update, Early Adoption	false
Accounting Standards Update 2017-01 [Member]
New Accounting Pronouncements or Change in Accounting Principle
Change in Accounting Principle, Accounting Standards Update, Adopted	true
Change in Accounting Principle, Accounting Standards Update, Adoption Date	Jan. 01, 2018
Change in Accounting Principle, Accounting Standards Update, Early Adoption	false
Change in Accounting Principle, Accounting Standards Update, Transition Option Elected	Prospective
Accounting Standards Update 2017-04 [Member]
New Accounting Pronouncements or Change in Accounting Principle
Change in Accounting Principle, Accounting Standards Update, Adopted	false
Change in Accounting Principle, Accounting Standards Update, Early Adoption	false
Accounting Standards Update 2017-08 [Member]
New Accounting Pronouncements or Change in Accounting Principle
Change in Accounting Principle, Accounting Standards Update, Adopted	true
Change in Accounting Principle, Accounting Standards Update, Adoption Date	Jan. 01, 2019
Change in Accounting Principle, Accounting Standards Update, Early Adoption	false
Change in Accounting Principle, Accounting Standards Update, Transition Option Elected	Modified Retrospective
Accounting Standards Update 2018-13 [Member]
New Accounting Pronouncements or Change in Accounting Principle
Change in Accounting Principle, Accounting Standards Update, Adopted	false
Change in Accounting Principle, Accounting Standards Update, Early Adoption	false
Accounting Standards Update 2019-05 [Member]
New Accounting Pronouncements or Change in Accounting Principle
Change in Accounting Principle, Accounting Standards Update, Adopted	false
Change in Accounting Principle, Accounting Standards Update, Early Adoption	false

Indicates (true false) whether accounting standards update was adopted.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 250
-SubTopic 10
-Section 50
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Date accounting standards update was adopted, in CCYY-MM-DD format.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 250
-SubTopic 10
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Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 250
-SubTopic 10
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-Paragraph 1
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+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 250
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+ References

No definition available.

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