Weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (i)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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- Definition

Unrecognized cost of unvested share-based awards, other than options, awarded to employees as compensation.

+ References

No definition available.

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- Definition

The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(2)(iii)(1)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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- Definition

The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(2)(iii)(1)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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- Definition

Fair value of share-based awards for which the grantee gained the right by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (d)(2)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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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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Stock Based Compensation - Restricted Stock and RSU Additional Information (Details) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Restricted Stock and Restricted Stock Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation cost	$ 43,016
Cost not yet recognized, period for recognition (in years)	2 years 8 months 12 days
Weighted-average fair value of restricted stock and RSUs granted (in dollars per share)	$ 48.97	$ 35.18	$ 26.47
Number of restricted stock units, vested	$ 10,761	$ 12,620	$ 11,393
Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted-average fair value of restricted stock and RSUs granted (in dollars per share)	$ 49.08
Number of restricted stock units, granted (in shares)	127,063
Liss Systems Limited \| Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of restricted stock units, granted (in shares)	33,459
Datasource Consulting, LLC \| Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of restricted stock units, granted (in shares)	93,604
IQR Consulting Inc. \| Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of restricted stock units, granted (in shares)	21,987
RPM Direct LLC and RPM Data Solutions LLC \| Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of restricted stock units, granted (in shares)		122,131