Summary of Significant Accounting Policies - Summary of Property and Equipment (Details)	6 Months Ended
Jun. 30, 2017
Leasehold Land And Buildings [Member] \| Investment Property [Member]
Property, Plant and Equipment [Line Items]
Expected useful life	50 years
Residual Value
Furniture and Fixtures [Member] \| Investment Property [Member]
Property, Plant and Equipment [Line Items]
Residual Value	5.00%
Furniture and Fixtures [Member] \| Investment Property [Member] \| Minimum [Member]
Property, Plant and Equipment [Line Items]
Expected useful life	3 years
Furniture and Fixtures [Member] \| Investment Property [Member] \| Maximum [Member]
Property, Plant and Equipment [Line Items]
Expected useful life	10 years
Furniture and Fixtures [Member] \| Plant And Equipment [Member]
Property, Plant and Equipment [Line Items]
Residual Value	5.00%
Furniture and Fixtures [Member] \| Plant And Equipment [Member] \| Minimum [Member]
Property, Plant and Equipment [Line Items]
Expected useful life	3 years
Furniture and Fixtures [Member] \| Plant And Equipment [Member] \| Maximum [Member]
Property, Plant and Equipment [Line Items]
Expected useful life	10 years
Office Equipment [Member] \| Investment Property [Member] \| Minimum [Member]
Property, Plant and Equipment [Line Items]
Expected useful life	3 years
Residual Value	5.00%
Office Equipment [Member] \| Investment Property [Member] \| Maximum [Member]
Property, Plant and Equipment [Line Items]
Expected useful life	10 years
Residual Value	10.00%
Office Equipment [Member] \| Plant And Equipment [Member] \| Minimum [Member]
Property, Plant and Equipment [Line Items]
Expected useful life	3 years
Residual Value	5.00%
Office Equipment [Member] \| Plant And Equipment [Member] \| Maximum [Member]
Property, Plant and Equipment [Line Items]
Expected useful life	10 years
Residual Value	10.00%
Leasehold Improvements [Member] \| Investment Property [Member]
Property, Plant and Equipment [Line Items]
Expected useful life, description	Over the shorter of estimated useful life or term of lease
Residual Value
Leasehold Improvements [Member] \| Plant And Equipment [Member]
Property, Plant and Equipment [Line Items]
Expected useful life, description	Over the shorter of estimated useful life or term of lease
Residual Value

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).

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-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

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-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

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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.

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- Definition

Stated as a percentage, the estimated or actual value of the asset at the end of its useful life or when it is no longer serviceable (cannot be used for its original purpose) divided by its [historical] capitalized cost.

+ References

No definition available.

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- 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.

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