Significant Accounting Polices - Additional Information (Detail) - USD ($)	3 Months Ended	12 Months Ended
Mar. 31, 2017	Dec. 31, 2016
Significant Accounting Polices Details [Abstract]
Cash in savings account	$ 1,800,000
Percentage of interest recognized from savings account investment	0.06%	0.06%
Interest income	$ 336	$ 4,188

Significant Accounting Polices Details [Abstract]

No definition available.

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- Definition

Amount of interest bearing deposits with no stated maturity, which may include passbook and statement savings accounts and money-market deposit accounts (MMDAs).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.12)
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

+ Details

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- Definition

Interest earned on deposits in United States money market accounts and other United States interest earning accounts.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 225
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-04.4)
-URI http://asc.fasb.org/extlink&oid=6879574&loc=d3e536633-122882

+ Details

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- Definition

The weighted average interest rate for domestic savings deposit liabilities.

+ References

No definition available.

+ Details

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