Discount rate used to calculate present value of future cash flows.

No definition available.

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- Definition

Weighted average amortization period of finite-lived intangible assets acquired either individually or as part of a group of assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 50
-Paragraph 1
-Subparagraph (a)(3)
-URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16265-109275

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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

The amount of goodwill arising from a business combination that is expected to be deductible for tax purposes.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 50
-Paragraph 1
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=35744584&loc=d3e6927-128479

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- Definition

Amount of consideration transferred, consisting of acquisition-date fair value of assets transferred by the acquirer, liabilities incurred by the acquirer, and equity interest issued by the acquirer.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 30
-Paragraph 7
-URI http://asc.fasb.org/extlink&oid=6911251&loc=d3e6578-128477

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-Publisher FASB
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- Definition

Amount of intangible assets, excluding goodwill, acquired at the acquisition date.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (c)
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- Definition

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (a)
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- Definition

The cash outflow associated with the acquisition of business during the period. The cash portion only of the acquisition price.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 13
-Subparagraph (b)
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Business Acquisitions (Narrative) (Details) - USD ($) $ in Thousands		3 Months Ended
	Nov. 30, 2016	Mar. 31, 2017	Dec. 31, 2016	Dec. 31, 2017
Business Acquisition [Line Items]
Goodwill			$ 85,463	$ 85,463
Placemeter [Member]
Business Acquisition [Line Items]
Total purchase price	$ 9,600
Purchase price, cash paid		$ 800	$ 8,800
Intangibles	6,000
Goodwill	3,742
Placemeter [Member] \| Technology [Member]
Business Acquisition [Line Items]
Intangibles	$ 5,500
Discount rate used to calculate present value of future cash flows ( in percentage)	15.00%
Acquired intangible assets, estimated useful life ( in years)	4 years
Placemeter [Member] \| Database [Member]
Business Acquisition [Line Items]
Intangibles	$ 200
Discount rate used to calculate present value of future cash flows ( in percentage)	15.00%
Acquired intangible assets, estimated useful life ( in years)	4 years
Placemeter [Member] \| Noncompete Agreements [Member]
Business Acquisition [Line Items]
Intangibles	$ 300
Discount rate used to calculate present value of future cash flows ( in percentage)	20.00%
Acquired intangible assets, estimated useful life ( in years)	3 years
Placemeter [Member] \| US Federal [Member]
Business Acquisition [Line Items]
Business Acquisition, Goodwill, Expected Tax Deductible Amount	$ 0
Placemeter [Member] \| State and Local Jurisdiction [Member]
Business Acquisition [Line Items]
Business Acquisition, Goodwill, Expected Tax Deductible Amount	$ 0