Acquisition and Disposals - Catlin - Transaction related costs (Details) $ in Thousands	6 Months Ended
Jun. 30, 2016 USD ($)
Business Combination, Separately Recognized Transactions [Line Items]
Liabilities at December 31, 2015	$ 57,289
Costs incurred in 2016	107,104
2016 payments	95,553
Liabilities at June 30, 2016	68,840
Severance related costs
Business Combination, Separately Recognized Transactions [Line Items]
Liabilities at December 31, 2015	16,127
Costs incurred in 2016	27,533
2016 payments	29,743
Liabilities at June 30, 2016	13,917
Retention and other compensation costs
Business Combination, Separately Recognized Transactions [Line Items]
Liabilities at December 31, 2015	16,969
Costs incurred in 2016	15,280
2016 payments	25,827
Liabilities at June 30, 2016	6,422
Facilities-related costs
Business Combination, Separately Recognized Transactions [Line Items]
Liabilities at December 31, 2015	818
Costs incurred in 2016	8,331
2016 payments	4,612
Liabilities at June 30, 2016	4,537
Consulting and other
Business Combination, Separately Recognized Transactions [Line Items]
Liabilities at December 31, 2015	23,375
Costs incurred in 2016	55,960
2016 payments	35,371
Liabilities at June 30, 2016	$ 43,964

Costs incurred to effect a business combination which have been expensed during the period. Such costs could include business integration costs, systems integration and conversion costs, and severance and other employee-related costs.

No definition available.

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- Definition

The amount of liabilities recognized recorded in a transaction with the acquiree for each transaction that is recognized separately from the acquisition of assets and assumptions of liabilities in the business combination.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (e)(3)
-URI http://asc.fasb.org/extlink&oid=56956515&loc=d3e1392-128463

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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.

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- Definition

Amount of cash payments made as the result of exit or disposal activities. Excludes payments associated with a discontinued operation or an asset retirement obligation.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=56944662&loc=d3e3602-108585

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