Future value of liabilities incurred by the acquirer to former owners of the acquiree.

No definition available.

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- Definition

Amortization expense recorded by the acquired companies since the acquisition date. Amortization expense is specific to acquired intangible assets.

+ References

No definition available.

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- Definition

Date when the business acquisition agreement was executed, in CCYY-MM-DD format.

+ References

No definition available.

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- Definition

With respect to a business combination completed during the period, this element provides a description of the business, other than the name, which may include the industry, size, products and other important information.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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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 increase (decrease) in the value of a contingent consideration liability, including, but not limited to, differences arising upon settlement.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
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-Topic 230
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- Definition

For contingent consideration arrangements recognized in connection with a business combination, this element represents an estimate of the high-end of the potential range (undiscounted) of the consideration which may be paid.

+ References

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- Definition

Amount of liability recognized arising from contingent consideration in a business combination.

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- Definition

Value of input used to measure contingent consideration liability from business combination.

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- Definition

This element represents the amount of earnings or loss of the acquiree since the acquisition date included in the consolidated income statement for the reporting period.

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- Definition

This element represents the amount of revenue of the acquiree since the acquisition date included in the consolidated income statement for the reporting period.

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- Definition

Amount recognized for assets, including goodwill, in excess of (less than) the aggregate liabilities assumed.

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The fair value of assets acquired in noncash investing or financing activities.

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Amount of liabilities classified as other, due after one year or the normal operating cycle, if longer.

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

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ACQUISITIONS AND DIVESTITURES (NARRATIVE) (Details) £ in Millions				3 Months Ended	6 Months Ended
	Apr. 30, 2018 GBP (£) item	Apr. 30, 2018 USD ($)	Mar. 31, 2018 USD ($)	Sep. 30, 2018 USD ($)	Jun. 30, 2019 USD ($)	Dec. 31, 2018 USD ($)	Apr. 30, 2018 USD ($) item
Business Acquisition [Line Items]
Other liabilities, noncurrent					$ 79,988,000	$ 126,532,000
Contingent Consideration, at fair value						2,363,000
Revenue of Acquirees since Acquisition Date, Actual					1,900,000
Income (loss) from operations of Acquirees since Acquisition Date, Actual					400,000
Acquired intangible amortization of acquirees since acquisition					$ 200,000
SCS
Business Acquisition [Line Items]
Payments to Acquire Businesses	£ 4.4	$ 6,100,000
Total purchase price							$ 9,511,000
Future Value of Liabilities Incurred From Business Acquisitions							2,900,000
Business Combination, Contingent Consideration Arrangements, Range of Outcomes, Value, High							4,100,000
Contingent Consideration, at fair value						$ 2,363,000	$ 2,700,000
SCS \| Discount Rate
Business Acquisition [Line Items]
Business combination contingent consideration measurement input \| item	4.7						4.7
SCS \| United Kingdom, Pounds
Business Acquisition [Line Items]
Business Combination, Contingent Consideration Arrangements, Range of Outcomes, Value, High \| £	£ 3.0
SCS \| TTEC Digital
Business Acquisition [Line Items]
Description of Acquired Entity	Strategic Communications ServicesOn April 30, 2018, the Company acquired all of the outstanding equity securities of Strategic Communications Services, Ltd ("SCS"). SCS provides services as a system integrator for multichannel contact center platforms, including CISCO. The Company offers in-house, managed and outsourced network, information, communications and contact center services to leading brands throughout Europe. This business has been integrated into the Company's TTEC Digital segment.	Strategic Communications ServicesOn April 30, 2018, the Company acquired all of the outstanding equity securities of Strategic Communications Services, Ltd ("SCS"). SCS provides services as a system integrator for multichannel contact center platforms, including CISCO. The Company offers in-house, managed and outsourced network, information, communications and contact center services to leading brands throughout Europe. This business has been integrated into the Company's TTEC Digital segment.
Increase (decrease) in contingent consideration payable				$ 210,000
BH
Business Acquisition [Line Items]
Date of Acquisition			Mar. 31, 2018
Description of Acquired Entity			Berkshire Hathaway Specialty ConciergeOn March 31, 2018, the Company, through its subsidiary Percepta, acquired certain assets from Berkshire Hathaway Specialty Concierge, LLC ("BH") related to a customer engagement center and the related customer contracts. This acquisition is being accounted for as a business combination. These assets have been integrated into the Company's TTEC Engage segment.
Total purchase price			$ 1
BH \| Customer Relationships [Member]
Business Acquisition [Line Items]
Fair Value of Assets Acquired			257,000
BH \| Lease Agreements [Member]
Business Acquisition [Line Items]
Fair Value of Assets Acquired			330,000
BH \| Fixed Assets
Business Acquisition [Line Items]
Fair Value of Assets Acquired			$ 98,000