Segment Reporting (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended
Mar. 31, 2015 segment	Mar. 31, 2014	Dec. 31, 2014
Segment Reporting
Number of operating segments	4us-gaap_NumberOfOperatingSegments
Segment reporting
Total revenues	$ 149,727us-gaap_Revenues	$ 137,609us-gaap_Revenues
Income (loss) before income tax expense (benefit)	22,340	18,420
Identifiable assets	1,529,451us-gaap_Assets	3,030,560us-gaap_Assets	1,350,849us-gaap_Assets
U.S. Operations
Segment reporting
Total revenues	80,454	75,607
Income (loss) before income tax expense (benefit)	11,056	10,256
Identifiable assets	1,098,740	1,068,577
Canadian Operations
Segment reporting
Total revenues	18,913	19,218
Income (loss) before income tax expense (benefit)	3,756	4,510
Identifiable assets	78,782	97,016
European Operations
Segment reporting
Total revenues	36,605	32,790
Income (loss) before income tax expense (benefit)	11,129	10,824
Identifiable assets	281,637	1,268,145
Asia Pacific Operations
Segment reporting
Total revenues	13,522	9,697
Income (loss) before income tax expense (benefit)	1,107	(1,818)
Identifiable assets	70,292	596,822
Corporate
Segment reporting
Total revenues	233	297
Income (loss) before income tax expense (benefit)	$ (4,708)	$ (5,352)

Sum of the carrying amounts as of the balance sheet date of all assets that are recognized. Assets are probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

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-Subparagraph (SX 210.5-02.18)

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

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Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

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-Number 210

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Reference 4: http://www.xbrl.org/2003/role/presentationRef

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Sum of operating profit and nonoperating income or expense before Income or Loss from equity method investments, income taxes, extraordinary items, and noncontrolling interest.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 235

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-Section S99

-Paragraph 1

-Subparagraph (SX 210.4-08.(h)(1)(i))

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- Definition

Number of operating segments. An operating segment is a component of an enterprise: (a) that engages in business activities from which it may earn revenues and incur expenses (including revenues and expenses relating to transactions with other components of the same enterprise), (b) whose operating results are regularly reviewed by the enterprise's chief operating decision maker to make decisions about resources to be allocated to the segment and assess its performance, and (c) for which discrete financial information is available. An operating segment may engage in business activities for which it has yet to earn revenues, for example, start-up operations may be operating segments before earning revenues.

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Amount of revenue recognized from goods sold, services rendered, insurance premiums, or other activities that constitute an earning process. Includes, but is not limited to, investment and interest income before deduction of interest expense when recognized as a component of revenue, and sales and trading gain (loss).

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 225

-SubTopic 10

-Section S99

-Paragraph 2

-Subparagraph (SX 210.5-03.1)

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