Segment Disclosures and Concentrations of Risk (Details)	12 Months Ended
Dec. 31, 2016 Segment Customer	Dec. 31, 2015 Customer
Segment Disclosures and Concentrations of Risk [Abstract]
Number of reportable segments \| Segment	1
Percentage of long-lived assets and revenue from external customers in united states	100.00%	100.00%
Customer Concentration Risk [Member] \| Revenues [Member]
Revenue, Major Customer [Line Items]
Number of largest individual customers	2	3
Customer Concentration Risk [Member] \| Revenues [Member] \| Customer One [Member]
Revenue, Major Customer [Line Items]
Percentage of concentration risk	20.40%	23.00%
Customer Concentration Risk [Member] \| Revenues [Member] \| Customer Two [Member]
Revenue, Major Customer [Line Items]
Percentage of concentration risk	15.20%	13.00%
Customer Concentration Risk [Member] \| Revenues [Member] \| Customer Three [Member]
Revenue, Major Customer [Line Items]
Percentage of concentration risk		10.00%
Customer Concentration Risk [Member] \| Accounts Receivable, Net [Member]
Revenue, Major Customer [Line Items]
Number of largest individual customers	1
Customer Concentration Risk [Member] \| Accounts Receivable, Net [Member] \| Customer One [Member]
Revenue, Major Customer [Line Items]
Percentage of concentration risk	28.00%

Represents the number of largest individual customers, including members of a marketing group.

No definition available.

Name:	tvty_NumberOfLargestIndividualCustomers
Namespace Prefix:	tvty_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Definition

Represents percentage of long-lived assets and revenue located in country of origin.

+ References

No definition available.

+ Details

Name:	tvty_SegmentReportingInformationPercentageOfLongLivedAssetsAndRevenuesLocatedInCountryOfOrigin
Namespace Prefix:	tvty_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 275
-SubTopic 10
-Section 50
-Paragraph 18
-URI http://asc.fasb.org/extlink&oid=64851502&loc=d3e6351-108592

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 20
-URI http://asc.fasb.org/extlink&oid=73719730&loc=d3e13531-108611

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 275
-SubTopic 10
-Section 50
-Paragraph 20
-URI http://asc.fasb.org/extlink&oid=64851502&loc=d3e6404-108592

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 21
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=73719730&loc=d3e13537-108611

+ Details

Name:	us-gaap_ConcentrationRiskPercentage1
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- 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.

+ Details

Name:	us-gaap_EntityWideRevenueMajorCustomerLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- 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.

+ References

No definition available.

+ Details

Name:	us-gaap_NumberOfReportableSegments
Namespace Prefix:	us-gaap_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- References

No definition available.

+ Details

Name:	us-gaap_SegmentReportingAbstract
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Details

Name:	us-gaap_ConcentrationRiskByTypeAxis=us-gaap_CustomerConcentrationRiskMember
Namespace Prefix:
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- Details

Name:	us-gaap_ConcentrationRiskByBenchmarkAxis=us-gaap_SalesRevenueNetMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_MajorCustomersAxis=tvty_CustomerOneMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_MajorCustomersAxis=tvty_CustomerTwoMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_MajorCustomersAxis=tvty_CustomerThreeMember
Namespace Prefix:
Data Type:	na
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- Details

Name:	us-gaap_ConcentrationRiskByBenchmarkAxis=us-gaap_AccountsReceivableMember
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