Balance Sheets (Parenthetical) (Detail) - $ / shares	Dec. 31, 2020	Dec. 31, 2019
Condensed Balance Sheet Statements Captions [Line Items]
Common shares, par value	$ 0.01	$ 0.01
Common shares, authorized	200,000,000	200,000,000
Common shares, issued	39,197,991	38,631,991
Common shares, outstanding	39,197,991	38,631,991
Parent Company
Condensed Balance Sheet Statements Captions [Line Items]
Common shares, par value	$ 0.01	$ 0.01
Common shares, authorized	200,000,000	200,000,000
Common shares, issued	39,197,991	38,631,991
Common shares, outstanding	39,197,991	38,631,991

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- Definition

Face amount or stated value per share of common stock.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(29))
-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

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- Definition

The maximum number of common shares permitted to be issued by an entity's charter and bylaws.

+ References

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- Definition

Total number of common shares of an entity that have been sold or granted to shareholders (includes common shares that were issued, repurchased and remain in the treasury). These shares represent capital invested by the firm's shareholders and owners, and may be all or only a portion of the number of shares authorized. Shares issued include shares outstanding and shares held in the treasury.

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- Definition

Number of shares of common stock outstanding. Common stock represent the ownership interest in a corporation.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=109259400&loc=d3e21463-112644

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(29))
-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

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