Summary Of Significant Accounting Policies (Schedule Of Basic And Diluted Income Per Common Share From Continuing Operations Calculations) (Details) (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended	9 Months Ended
Mar. 31, 2015	Mar. 31, 2014	Mar. 31, 2015	Mar. 31, 2014
Accounting Policies [Abstract]
Income from continuing operations	$ 20,403	$ 18,900	$ 76,118	$ 80,085
Income from continuing operations available to participating securities	(26)	(21)	(109)	(139)
Income from continuing operations available to common shareholders	$ 20,377	$ 18,879	$ 76,009	$ 79,946
Weighted average common shares outstanding - basic (in shares)	27,303	27,261	27,294	27,258
Incremental share effect from:
Nonparticipating restricted stock (in shares)	2	2	3	3
Stock-settled stock appreciation rights (in shares)	25	34	26	42
Weighted average common shares outstanding - diluted (in shares)	27,330	27,297	27,323	27,303
Income per common share from continuing operations - basic and diluted (in dollars per share)	$ 0.75	$ 0.69	$ 2.78	$ 2.93

Summary Of Significant Accounting Policies (Schedule Of Basic And Diluted Income Per Common Share From Continuing Operations Calculations) (Details) (USD $)
In Thousands, except Per Share data, unless otherwise specified

3 Months Ended

9 Months Ended

Mar. 31, 2015

Mar. 31, 2014

Mar. 31, 2015

Mar. 31, 2014

Accounting Policies [Abstract]

Income from continuing operations

$ 20,403us-gaap_IncomeLossFromContinuingOperationsIncludingPortionAttributableToNoncontrollingInterest

$ 18,900us-gaap_IncomeLossFromContinuingOperationsIncludingPortionAttributableToNoncontrollingInterest

$ 76,118us-gaap_IncomeLossFromContinuingOperationsIncludingPortionAttributableToNoncontrollingInterest

$ 80,085us-gaap_IncomeLossFromContinuingOperationsIncludingPortionAttributableToNoncontrollingInterest

Income from continuing operations available to participating securities

(26)us-gaap_ParticipatingSecuritiesDistributedAndUndistributedEarningsLossDiluted

(21)us-gaap_ParticipatingSecuritiesDistributedAndUndistributedEarningsLossDiluted

(109)us-gaap_ParticipatingSecuritiesDistributedAndUndistributedEarningsLossDiluted

(139)us-gaap_ParticipatingSecuritiesDistributedAndUndistributedEarningsLossDiluted

Income from continuing operations available to common shareholders

$ 20,377lanc_IncomeFromContinuingOperationsAvailableToCommonShareholders

$ 18,879lanc_IncomeFromContinuingOperationsAvailableToCommonShareholders

$ 76,009lanc_IncomeFromContinuingOperationsAvailableToCommonShareholders

$ 79,946lanc_IncomeFromContinuingOperationsAvailableToCommonShareholders

Weighted average common shares outstanding - basic (in shares)

27,303us-gaap_WeightedAverageNumberOfSharesOutstandingBasic

27,261us-gaap_WeightedAverageNumberOfSharesOutstandingBasic

27,294us-gaap_WeightedAverageNumberOfSharesOutstandingBasic

27,258us-gaap_WeightedAverageNumberOfSharesOutstandingBasic

Incremental share effect from:

Nonparticipating restricted stock (in shares)

2us-gaap_IncrementalCommonSharesAttributableToNonvestedSharesWithForfeitableDividends

3us-gaap_IncrementalCommonSharesAttributableToNonvestedSharesWithForfeitableDividends

Stock-settled stock appreciation rights (in shares)

25us-gaap_IncrementalCommonSharesAttributableToShareBasedPaymentArrangements

34us-gaap_IncrementalCommonSharesAttributableToShareBasedPaymentArrangements

26us-gaap_IncrementalCommonSharesAttributableToShareBasedPaymentArrangements

42us-gaap_IncrementalCommonSharesAttributableToShareBasedPaymentArrangements

Weighted average common shares outstanding - diluted (in shares)

27,330us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding

27,297us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding

27,323us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding

27,303us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding

Income per common share from continuing operations - basic and diluted (in dollars per share)

$ 0.75us-gaap_IncomeLossFromContinuingOperationsPerBasicAndDilutedShare

$ 0.69us-gaap_IncomeLossFromContinuingOperationsPerBasicAndDilutedShare

$ 2.78us-gaap_IncomeLossFromContinuingOperationsPerBasicAndDilutedShare

$ 2.93us-gaap_IncomeLossFromContinuingOperationsPerBasicAndDilutedShare

- Definition

Aggregate of income from continuing operations distributed and income from continuing operations allocated to common shareholders under the two-class method to the extent that participating securities may share in earnings as if all of the earnings for the period had been distributed.

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This element represents the income or loss from continuing operations attributable to the economic entity which may also be defined as revenue less expenses and taxes from ongoing operations before extraordinary items, and noncontrolling interest.

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The amount of net income (loss) from continuing operations per each basic and diluted share of common stock or unit when the per share amount is the same for both basic and diluted shares.

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- Definition

Nonvested equity-based payment awards that contain forfeitable rights to dividends or dividend equivalents (whether paid or unpaid) that result in incremental common shares.

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Additional shares included in the calculation of diluted EPS as a result of the potentially dilutive effect of share based payment arrangements using the treasury stock method.

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Amount of earnings (loss) distributed and earnings (loss) allocated to participating securities for the diluted earnings (loss) per share or per unit calculation under the two-class method.

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The average number of shares or units issued and outstanding that are used in calculating diluted EPS or earnings per unit (EPU), determined based on the timing of issuance of shares or units in the period.

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Number of [basic] shares or units, after adjustment for contingently issuable shares or units and other shares or units not deemed outstanding, determined by relating the portion of time within a reporting period that common shares or units have been outstanding to the total time in that period.

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