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Nature of Operations and Summary of Significant Accounting Policies - Summary of Property and Equipment (Details)	12 Months Ended
	Dec. 31, 2019
Office Leaseholds [Member] | Plant And Equipment [Member]
Property, Plant and Equipment [Line Items]
Estimated useful life	27 years
Office Leaseholds [Member] | Real Estate Held for Investment [Member]
Property, Plant and Equipment [Line Items]
Estimated useful life	50 years
Furniture and Fixtures [Member] | Plant And Equipment [Member] | Minimum [Member]
Property, Plant and Equipment [Line Items]
Estimated useful life	3 years
Furniture and Fixtures [Member] | Plant And Equipment [Member] | Maximum [Member]
Property, Plant and Equipment [Line Items]
Estimated useful life	10 years
Furniture and Fixtures [Member] | Real Estate Held for Investment [Member] | Minimum [Member]
Property, Plant and Equipment [Line Items]
Estimated useful life	3 years
Furniture and Fixtures [Member] | Real Estate Held for Investment [Member] | Maximum [Member]
Property, Plant and Equipment [Line Items]
Estimated useful life	10 years
Office Equipment [Member] | Plant And Equipment [Member] | Minimum [Member]
Property, Plant and Equipment [Line Items]
Estimated useful life	3 years
Office Equipment [Member] | Plant And Equipment [Member] | Maximum [Member]
Property, Plant and Equipment [Line Items]
Estimated useful life	10 years
Office Equipment [Member] | Real Estate Held for Investment [Member] | Minimum [Member]
Property, Plant and Equipment [Line Items]
Estimated useful life	3 years
Office Equipment [Member] | Real Estate Held for Investment [Member] | Maximum [Member]
Property, Plant and Equipment [Line Items]
Estimated useful life	10 years
Leasehold Improvements [Member] | Plant And Equipment [Member]
Property, Plant and Equipment [Line Items]
Estimated useful life, description	Over the shorter of estimated useful life or term of lease
Leasehold Improvements [Member] | Real Estate Held for Investment [Member]
Property, Plant and Equipment [Line Items]
Estimated useful life, description	Shorter of the estimated useful life or term of lease

X

- Definition

Describes the periods of time over which an entity anticipates to receive utility from its property, plant and equipment (that is, the periods of time over which an entity allocates the initial cost of its property, plant and equipment).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 360
-SubTopic 10
-Section 35
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=68071081&loc=d3e1205-110223

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section 50
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=84158767&loc=d3e18780-107790

+ Details

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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X

- Definition

Useful life of long lived, physical assets used in the normal conduct of business and not intended for resale, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Examples include, but not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment.

+ References

No definition available.

+ Details

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- Details

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