Name:	kala_AccruedContractManufacturing
Namespace Prefix:	kala_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

Accrued revenue reserves.

No definition available.

Name:	kala_AccruedRevenueReserves
Namespace Prefix:	kala_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

Carrying values as of the balance sheet date of payable towards development costs, due within one year or within the normal operating cycle if longer.

No definition available.

Name:	kala_DevelopmentCostsCurrent
Namespace Prefix:	kala_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

Amount of other accrued expenses.

No definition available.

Name:	kala_OtherAccruedExpensesCurrent
Namespace Prefix:	kala_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- References

No definition available.

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

Carrying value as of the balance sheet date of obligations incurred and payable, pertaining to costs that are statutory in nature, are incurred on contractual obligations, or accumulate over time and for which invoices have not yet been received or will not be rendered. Examples include taxes, interest, rent and utilities. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.20)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480566/210-10-S99-1

Name:	us-gaap_AccruedLiabilitiesCurrent
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Data Type:	xbrli:monetaryItemType
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Period Type:	instant

Carrying value as of the balance sheet date of obligations incurred through that date and payable for professional fees, such as for legal and accounting services received. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

Name:	us-gaap_AccruedProfessionalFeesCurrent
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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

Total of the carrying values as of the balance sheet date of obligations incurred through that date and payable for obligations related to services received from employees, such as accrued salaries and bonuses, payroll taxes and fringe benefits. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).