Capitalized debt issuance cost.

No definition available.

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Namespace Prefix:	lnth_
Data Type:	xbrli:monetaryItemType
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Period Type:	instant

- Definition

Cost associated with debt modification.

+ References

No definition available.

+ Details

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Period Type:	duration

- Definition

Debt instrument additional borrowing capacity.

+ References

No definition available.

+ Details

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

- Definition

Debt instrument discount amount.

+ References

No definition available.

+ Details

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

- Definition

Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 4
-Subparagraph (b)(1)
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-Publisher FASB
-Name Accounting Standards Codification
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-Section S99
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-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
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-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(16))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

+ Details

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

- Definition

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

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 2
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+ Details

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Period Type:	instant

- 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

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Period Type:	duration

- Definition

Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

+ Details

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- Definition

Difference between the fair value of payments made and the carrying amount of debt which is extinguished prior to maturity.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 50
-Section 40
-Paragraph 4
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- Definition

The cash outflow during the period from the repayment of aggregate short-term and long-term debt. Excludes payment of capital lease obligations.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
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-Paragraph 15
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Financing Arrangements - Additional Information (Detail) - USD ($)		12 Months Ended
	Mar. 30, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Debt Instrument [Line Items]
Loss on extinguishment of debt and debt retirement costs	$ 2,200,000	$ 0	$ (2,442,000)	$ (1,896,000)
Third-party costs associated with modified debt	1,700,000
Debt issuance costs	1,600,000
2015 Term Facility
Debt Instrument [Line Items]
Debt instrument, face amount	$ 365,000,000
Debt instrument, term (in years)	7 years
Cash paid during the execution of refinancing	$ 15,300,000
Revolving Line of Credit
Debt Instrument [Line Items]
Debt instrument, face amount	$ 75,000,000
Debt instrument, term (in years)	5 years
2017 Term Facility
Debt Instrument [Line Items]
Debt instrument, face amount	$ 275,000,000
Debt instrument, term (in years)	5 years
Debt instrument, discount amount	$ 700,000
Increase in aggregate principal amount	75,000,000
Aggregate principal amount outstanding		$ 270,187,000
Asset Based Loan (ABL) Facility
Debt Instrument [Line Items]
Debt instrument, face amount	$ 50,000,000
Debt instrument, term (in years)	5 years