Contingencies and commitments.

No definition available.

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- Definition

Severance costs and stock based compensation costs.

+ References

No definition available.

+ Details

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- Definition

Carrying amount (including both current and noncurrent portions of the accrual) as of the balance sheet date pertaining to a specified type of cost associated with exit from or disposal of business activities or restructuring pursuant to a duly authorized plan.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 420
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SAB TOPIC 5.P.4(b))
-URI http://asc.fasb.org/extlink&oid=27011515&loc=d3e140904-122747

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 420
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (b)(2)
-URI http://asc.fasb.org/extlink&oid=6394359&loc=d3e17939-110869

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- Definition

Additional share-based compensation cost recognized as a result of an occurrence of an event that accelerates its recognition.

+ References

No definition available.

+ Details

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- Definition

Liability for amount due employees, in addition to wages and any other money that employers owe employees, when their employment ends through a layoff or other termination. For example, a company may provide involuntarily terminated employees with a lump sum payment equal to one week's salary for every year of employment.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Other Postemployment Benefits
-URI http://asc.fasb.org/extlink&oid=6519534

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- Details

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Commitments and Contingencies - Additional Information (Detail) - Employee Severance - USD ($) $ in Millions	3 Months Ended
	Jun. 30, 2017	Mar. 31, 2017
Contingencies And Commitments [Line Items]
Aggregate separation charge		$ 11.5
Scenario Forecast [Member]
Contingencies And Commitments [Line Items]
Severance costs and stock-based compensation expense	$ 5.0
Accounts Payable and Accrued Expenses [Member]
Contingencies And Commitments [Line Items]
Accrued separation charge		8.2
Management Transition [Member]
Contingencies And Commitments [Line Items]
Aggregate separation charge		9.4
Stock-based compensation expense		3.3
Other Contractual Staffing Reductions [Member]
Contingencies And Commitments [Line Items]
Aggregate separation charge		$ 2.1