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Significant Accounting Policies - Impact of new financial accounting standards (Details) $ in Billions	3 Months Ended
	Mar. 31, 2021 USD ($) segment
Significant Accounting Policies
Value of company | $	$ 10.8
Number of operating segments | segment	3

X

- Definition

Assets under care held for customers, that are not included in the Company's consolidated financial statements.

+ References

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- References

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- Definition

Number of operating segments. An operating segment is a component of an enterprise: (a) that engages in business activities from which it may earn revenues and incur expenses (including revenues and expenses relating to transactions with other components of the same enterprise), (b) whose operating results are regularly reviewed by the enterprise's chief operating decision maker to make decisions about resources to be allocated to the segment and assess its performance, and (c) for which discrete financial information is available. An operating segment may engage in business activities for which it has yet to earn revenues, for example, start-up operations may be operating segments before earning revenues.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 18
-URI http://asc.fasb.org/extlink&oid=120311839&loc=d3e8672-108599

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