Condensed Financial Information of Registrant (Parent Only) Balance Sheets (Parenthetical) (Detail)	Dec. 31, 2016 $ / shares shares	Nov. 07, 2016 $ / shares	Dec. 31, 2015 $ / shares shares	Dec. 31, 2015 € / shares shares
Condensed Financial Statements, Captions [Line Items]
Ordinary shares, par value \| $ / shares	$ 0.0001		$ 0.0001
Ordinary shares, shares authorized	900,000,000		900,000,000	900,000,000
Ordinary Shares A
Condensed Financial Statements, Captions [Line Items]
Ordinary shares, par value \| $ / shares		$ 0.0001
Ordinary shares, shares issued	13,436,548		16,424,546	16,424,546
Ordinary shares, shares outstanding	13,436,548		13,313,751	13,313,751
Treasury shares, cost	0		3,110,795	3,110,795
Ordinary Shares B
Condensed Financial Statements, Captions [Line Items]
Ordinary shares, par value \| $ / shares		$ 0.0001
Ordinary shares, shares issued	4,133,366		4,133,366	4,133,366
Ordinary shares, shares outstanding	4,133,366		4,133,366	4,133,366
Parent Company
Condensed Financial Statements, Captions [Line Items]
Ordinary shares, par value \| $ / shares	$ 0.0001		$ 0.0001
Ordinary shares, shares authorized	900,000,000		900,000,000	900,000,000
Deferred shares, par value \| € / shares				€ 1
Deferred shares, shares authorized			40,000	40,000
Deferred shares, shares issued			40,000	40,000
Deferred shares, shares outstanding			40,000	40,000
Preferred shares, par value \| $ / shares	$ 0.0001		$ 0.0001
Preferred shares, shares authorized	100,000,000		100,000,000	100,000,000
Preferred shares, shares issued	0		0	0
Preferred shares, shares outstanding	0		0	0
Parent Company \| Ordinary Shares A
Condensed Financial Statements, Captions [Line Items]
Ordinary shares, shares issued	13,436,548		16,424,546	16,424,546
Ordinary shares, shares outstanding	13,436,548		13,313,751	13,313,751
Treasury shares, cost			3,110,795	3,110,795
Parent Company \| Ordinary Shares B
Condensed Financial Statements, Captions [Line Items]
Ordinary shares, shares issued	4,133,366		4,133,366	4,133,366
Ordinary shares, shares outstanding	4,133,366		4,133,366	4,133,366

Deferred Shares Par Value

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Deferred Shares Shares Authorized

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No definition available.

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- Definition

Deferred Shares Shares Issued

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No definition available.

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- Definition

Deferred Shares Shares Outstanding

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No definition available.

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- Definition

Face amount or stated value per share of common stock.

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

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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://www.xbrl.org/2003/role/presentationRef
-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=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21463-112644

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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.

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No definition available.

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Face amount or stated value per share of preferred stock nonredeemable or redeemable solely at the option of the issuer.

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The maximum number of nonredeemable preferred shares (or preferred stock redeemable solely at the option of the issuer) permitted to be issued by an entity's charter and bylaws.

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Total number of nonredeemable preferred shares (or preferred stock redeemable solely at the option of the issuer) issued to shareholders (includes related preferred shares that were issued, repurchased, and remain in the treasury). May be all or portion of the number of preferred shares authorized. Excludes preferred shares that are classified as debt.

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Aggregate share number for all nonredeemable preferred stock (or preferred stock redeemable solely at the option of the issuer) held by stockholders. Does not include preferred shares that have been repurchased.

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Number of common and preferred shares that were previously issued and that were repurchased by the issuing entity and held in treasury on the financial statement date. This stock has no voting rights and receives no dividends.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.29,30)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 30
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6405813&loc=d3e23239-112655

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