Convertible Note Agreements - Related Party (Schedule of Debt) (Details)	Jun. 30, 2018 USD ($)
Related parties
Convertible notes payable, related, principal	$ 1,000,000
Convertible notes payable, related, unamortized discount	(25,725)
Convertible notes payable, related, net	974,275
Convertible line of credit, related, principal	5,895,000
Convertible line of credit, related, unamortized discount	(472,920)
Convertible line of credit, related, net	5,422,080
Less current portion, related, principal
Less current portion, related, unamortized portion
Less current portion, related, net
Convertible and nonconvertible note payable, net of current portion, principal	6,895,000
Convertible and nonconvertible note payable, net of current portion, unamortized discount	(498,645)
Convertible and nonconvertible note payable, net of current portion, net	$ 6,396,355

Convertible and notes payable from related parties aggregate amount.

No definition available.

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Period Type:	instant

- Definition

The amount of convertible and notes payable debt discount related to third parties that has not yet been amortized.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
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Period Type:	instant

- Definition

The amount of convertible line of credit, current and non-current, from related parties.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
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- Definition

Convertible line of credit from related parties aggregate amount.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
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- Definition

The amount of covertible debt, current and noncurrent, discount from related parties.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
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- Definition

Convertible notes payable from related parties aggregate amount.

+ References

No definition available.

+ Details

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Namespace Prefix:	gltc_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Longterm debt current with related parties, net.

+ References

No definition available.

+ Details

Name:	gltc_LongtermDebtCurrentNet
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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The amount of discount that has not yet been recognized, convertible and notes payable from related parties.

+ References

No definition available.

+ Details

Name:	gltc_LongtermDebtCurrentUnamortizedDiscount
Namespace Prefix:	gltc_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- References

No definition available.

+ Details

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Balance Type:	na
Period Type:	duration

- Definition

The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(22))
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-Name Accounting Standards Codification
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-SubTopic 210
-Section S99
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-Subparagraph (SX 210.9-03(16))
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-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
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-Section S99
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-Subparagraph (SX 210.7-03(16))
-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

+ Details

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- Definition

Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt, classified as current. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

+ References

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Carrying value as of the balance sheet date of notes payable (with maturities initially due after one year or beyond the operating cycle if longer), excluding current portion.

+ References

+ Details

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Period Type:	instant

- Definition

The amount for notes payable (written promise to pay), payable to related parties, which are due after one year (or one business cycle).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 850
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=6457730&loc=d3e39549-107864

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08.(k)(1))
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

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-Publisher FASB
-Name Accounting Standards Codification
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-Section S99
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-Subparagraph (SX 210.5-02.23)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

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