Subsequent Event (Details) - Subsequent Event [Member] - Credit Agreement [Member]	Apr. 21, 2017 USD ($)
Subsequent Event [Line Items]
Initiation date	Apr. 21, 2017
Maturity date	Apr. 21, 2022
Minimum [Member]
Subsequent Event [Line Items]
Unused commitment fee percentage	0.20%
Maximum [Member]
Subsequent Event [Line Items]
Unused commitment fee percentage	0.50%
Federal Funds Rate [Member]
Subsequent Event [Line Items]
Basis spread on variable rate	0.50%
LIBOR [Member] \| Minimum [Member]
Subsequent Event [Line Items]
Variable rate basis	0.00%
Margin rate	1.50%
LIBOR [Member] \| Maximum [Member]
Subsequent Event [Line Items]
Margin rate	2.75%
One-Month LIBOR [Member]
Subsequent Event [Line Items]
Basis spread on variable rate	1.00%
Base Rate [Member] \| Minimum [Member]
Subsequent Event [Line Items]
Margin rate	0.50%
Base Rate [Member] \| Maximum [Member]
Subsequent Event [Line Items]
Margin rate	1.75%
Revolving Credit Facility [Member]
Subsequent Event [Line Items]
Maximum borrowing capacity	$ 100,000,000
Sublimit for Swingline Loans [Member]
Subsequent Event [Line Items]
Maximum borrowing capacity	25,000,000
Sublimit for Letters of Credit [Member]
Subsequent Event [Line Items]
Maximum borrowing capacity	75,000,000
Term Loan A Facility [Member]
Subsequent Event [Line Items]
Debt instrument, face amount	70,000,000
Term Loan A Facility [Member] \| First 12 Quarters Following the Closing [Member]
Subsequent Event [Line Items]
Periodic principal payment	875,000
Term Loan A Facility [Member] \| Remaining Quarters Prior to Maturity [Member]
Subsequent Event [Line Items]
Periodic principal payment	1,312,500
Delayed Draw Term Loan Facility [Member]
Subsequent Event [Line Items]
Debt instrument, face amount	$ 150,000,000
Delayed Draw Term Loan Facility [Member] \| First 12 Quarters Following the Closing [Member]
Subsequent Event [Line Items]
Periodic principal payment as percentage of aggregate principal amount	1.25%
Delayed Draw Term Loan Facility [Member] \| Remaining Quarters Prior to Maturity [Member]
Subsequent Event [Line Items]
Periodic principal payment as percentage of aggregate principal amount	1.875%
Uncommitted Incremental Accordion Facility [Member]
Subsequent Event [Line Items]
Maximum borrowing capacity	$ 100,000,000

Refers to the margin rate on the debt instrument.

No definition available.

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

- Definition

Amount of the required periodic payments expressed as a percent of the original principal amount of debt instrument.

+ References

No definition available.

+ Details

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

- Definition

The reference rate for the variable rate of the debt instrument, such as LIBOR or the US Treasury rate and the maturity of the reference rate used, such as three months or six months LIBOR.

+ References

No definition available.

+ Details

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

- Definition

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

+ References

No definition available.

+ Details

Name:	us-gaap_DebtInstrumentBasisSpreadOnVariableRate1
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Face (par) amount of debt instrument at time of issuance.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 55
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=64930739&loc=d3e28878-108400

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=64930785&loc=d3e28551-108399

+ Details

Name:	us-gaap_DebtInstrumentFaceAmount
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Date when the debt instrument is scheduled to be fully repaid, in CCYY-MM-DD format.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.22(a)(2))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:dateItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount of the required periodic payments applied to principal.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.22)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Date the credit facility first became available, in CCYY-MM-DD format.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.19(b),22(b))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:dateItemType
Balance Type:	na
Period Type:	duration

- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.19(b),22(b))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The fee, expressed as a percentage of the line of credit facility, for available but unused credit capacity under the credit facility.

+ References

No definition available.

+ Details

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

- Definition

Detail information of subsequent event by type. User is expected to use existing line items from elsewhere in the taxonomy as the primary line items for this disclosure, which is further associated with dimension and member elements pertaining to a subsequent event.

+ References

No definition available.

+ Details

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- Details

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- Details

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- Details

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Namespace Prefix:
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- Details

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Namespace Prefix:
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- Details

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Namespace Prefix:
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- Details

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Namespace Prefix:
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- Details

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Namespace Prefix:
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Balance Type:
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- Details

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Namespace Prefix:
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- Details

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- Details

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- Details

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Namespace Prefix:
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- Details

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Namespace Prefix:
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- Details

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