Goodwill and Other Intangible Assets - Additional Information (Detail)	12 Months Ended
Dec. 31, 2018 Segment
Goodwill [Line Items]
Number of operating groups, which represent our reportable segments	5
Fair value of reporting units exceeded	100.00%
NCSA [Member]
Goodwill [Line Items]
Discount rate assumption in deriving the reporting unit’s fair value	28.00%
Compound annual growth rate assumption in deriving the reporting unit’s fair value	13.00%
Terminal growth rate assumption in deriving the reporting unit’s fair value	2.00%
EARC [Member]
Goodwill [Line Items]
Discount rate assumption in deriving the reporting unit’s fair value	32.00%
Compound annual growth rate assumption in deriving the reporting unit’s fair value	76.00%
Terminal growth rate assumption in deriving the reporting unit’s fair value	2.00%
Technology [Member]
Goodwill [Line Items]
Discount rate assumption in deriving the reporting unit’s fair value	14.50%
Compound annual growth rate assumption in deriving the reporting unit’s fair value	11.00%
Terminal growth rate assumption in deriving the reporting unit’s fair value	2.00%
APAC [Member]
Goodwill [Line Items]
Discount rate assumption in deriving the reporting unit’s fair value	25.00%
Compound annual growth rate assumption in deriving the reporting unit’s fair value	45.00%
Terminal growth rate assumption in deriving the reporting unit’s fair value	2.00%

Reporting unit compound annual growth rate assumption used in deriving fair value.

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- Definition

Reporting unit, discount rate assumption used in deriving fair value.

+ References

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- Definition

Reporting unit, terminal growth rate assumption used in deriving fair value.

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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.

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No definition available.

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- Definition

Number of segments reported by the entity. A reportable segment is a component of an entity for which there is an accounting requirement to report separate financial information on that component in the entity's financial statements.

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- Definition

Percentage of fair value of reporting unit in excess of carrying amount.

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No definition available.

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