Fair value of financial instruments - Rollforward of Level 3 liabilities (Details) $ in Thousands	6 Months Ended
Jun. 30, 2016 USD ($)
Rollforward of Level 3 liabilities
Change in fair value of contingent consideration	$ 2,271
Fair Value \| Level 3
Rollforward of Level 3 liabilities
Initial recognition of contingent consideration	293,000
Contingent consideration earned during the period	(1,271)
Change in fair value of contingent consideration	2,271
Balance at end of period	$ 294,000

Amount of increase in the value of total contingent consideration liability attributable to business acquisitions during the period.

No definition available.

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- Definition

Amount of decrease in the value of a contingent consideration liability attributable to consideration earned by the acquiree in a business combination.

+ References

No definition available.

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- References

No definition available.

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- Definition

Amount of increase (decrease) in the value of a contingent consideration liability, including, but not limited to, differences arising upon settlement.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 50
-Paragraph 4
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=35744584&loc=d3e7008-128479

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- Definition

Fair value of financial obligations, including, but not limited to, debt instruments, derivative liabilities, federal funds purchased and sold under agreements to repurchase, securities loaned or sold under agreements to repurchase, financial instruments sold not yet purchased, guarantees, line of credit, loans and notes payable, servicing liability, and trading liabilities.

+ References

No definition available.

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