Related Party Transactions (Details) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
Dec. 31, 2015	Dec. 31, 2014
Related Party Transaction [Line Items]
Payments for repurchase of common stock	$ 12,997	$ 31,395
Chairman Of The Board Of Directors [Member]
Related Party Transaction [Line Items]
Shares of common stock cancelled		400,000
Payments for repurchase of common stock		$ 8,800
Repurchase of common stock, average price per share		$ 21.92
CAIJ [Member]
Related Party Transaction [Line Items]
Ownership percentage by parent	80.00%
Ownership percentage by noncontrolling interest	20.00%

Repurchase Of Common Stock, Average Price Per Share

No definition available.

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- Definition

The equity interest of noncontrolling shareholders, partners or other equity holders in consolidated entity.

+ References

No definition available.

+ Details

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- Definition

The parent entity's interest in net assets of the subsidiary, expressed as a percentage.

+ References

No definition available.

+ Details

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- Definition

The cash outflow to reacquire common stock during the period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 15
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3291-108585

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Financing Activities
-URI http://asc.fasb.org/extlink&oid=6513228

+ 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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- Definition

Number of shares of common and preferred stock retired from treasury during the period.

+ References

Reference 1: 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

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 04
-Article 3

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- Details

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