Acquisitions, divestitures and subsequent events (Details Textuals) (MSC Group [Member], USD $) In Thousands, unless otherwise specified	0 Months Ended
Oct. 01, 2013
MSC Group [Member]
Subsequent Event [Line Items]
Date of subsequent event	Oct. 01, 2013
Description of subsequent event	the Company acquired a controlling interest in MSC Investoren GmbH ("MSC Group")
Revenue reported by MSC Group for calendar year 2012	$ 450,000

Total revenue reported by the acquired entity for its previous full fiscal year before the business acquisition.

No definition available.

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- Definition

Describes the event or transaction that occurred between the balance sheet date and the date the financial statements are issued or available to be issued.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 855

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=6842918&loc=SL6314017-165662

+ Details

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- Definition

Date the event occurred after the balance sheet date but before financial statements are issues or available to be issued, in CCYY-MM-DD format.

+ References

+ Details

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