Loans with Contingent Obligation, Number of Loans

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Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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- Definition

Amount of rent expense incurred for leased assets, including but not limited to, furniture and equipment, that is not directly or indirectly associated with the manufacture, sale or creation of a product or product line.

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- Definition

The total amount of the contingent obligation under letters of credit outstanding as of the reporting date.

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Weighted average interest rate of long-term debt outstanding.

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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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- Definition

Amount of loss contingency liability.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 450
-SubTopic 20
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=25496072&loc=d3e14326-108349

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Reflects the estimated amount of loss from the specified contingency as of the balance sheet date.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 450
-SubTopic 20
-Section 50
-Paragraph 4
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=25496072&loc=d3e14435-108349

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 450
-SubTopic 20
-Section 50
-Paragraph 9
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=25496072&loc=d3e14557-108349

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Commitments and Contingent Liabilities - Additional Information (Details)	3 Months Ended
	Mar. 31, 2017 USD ($) loan	Mar. 31, 2016 USD ($)	Jul. 08, 2016 EUR (€)
Occupancy and Equipment Rentals
Loss Contingencies [Line Items]
Rental expense under the office leases	$ 4,700,000	$ 6,100,000
Revolving Credit Facility
Loss Contingencies [Line Items]
Weighted average interest rate	4.42%
Debt term	3 years
Trading Activities on Euronext
Loss Contingencies [Line Items]
Loss contingency reserve \| €			€ 400,000
Guarantee Obligation
Loss Contingencies [Line Items]
Letters of credit obligation	$ 10,200,000
Indemnification Agreement
Loss Contingencies [Line Items]
Number of loans with contingent potential obligation \| loan	40
Indemnification Agreement \| Maximum
Loss Contingencies [Line Items]
Potential losses on loans	$ 10,100,000.0