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	6 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2014	Dec. 31, 2013
Accounting Policies [Abstract]
Income from continuing operations	$ 32,954	$ 37,133	$ 55,715	$ 61,185
Income from continuing operations available to participating securities	(57)	(51)	(95)	(83)
Income from continuing operations available to common shareholders	$ 32,897	$ 37,082	$ 55,620	$ 61,102
Weighted average common shares outstanding - basic (in shares)	27,294	27,244	27,290	27,256
Incremental share effect from:
Nonparticipating restricted stock (in shares)	3	3	4	4
Stock-settled stock appreciation rights (in shares)	26	52	25	46
Weighted average common shares outstanding - diluted (in shares)	27,323	27,299	27,319	27,306
Income per common share from continuing operations - basic (in dollars per share)	$ 1.21	$ 1.36	$ 2.04	$ 2.24
Income per common share from continuing operations - diluted (in dollars per share)	$ 1.20	$ 1.36	$ 2.04	$ 2.24

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

6 Months Ended

Dec. 31, 2014

Dec. 31, 2013

Dec. 31, 2014

Dec. 31, 2013

Accounting Policies [Abstract]

Income from continuing operations

$ 32,954us-gaap_IncomeLossFromContinuingOperationsIncludingPortionAttributableToNoncontrollingInterest

$ 37,133us-gaap_IncomeLossFromContinuingOperationsIncludingPortionAttributableToNoncontrollingInterest

$ 55,715us-gaap_IncomeLossFromContinuingOperationsIncludingPortionAttributableToNoncontrollingInterest

$ 61,185us-gaap_IncomeLossFromContinuingOperationsIncludingPortionAttributableToNoncontrollingInterest

Income from continuing operations available to participating securities

(57)us-gaap_ParticipatingSecuritiesDistributedAndUndistributedEarningsLossDiluted

(51)us-gaap_ParticipatingSecuritiesDistributedAndUndistributedEarningsLossDiluted

(95)us-gaap_ParticipatingSecuritiesDistributedAndUndistributedEarningsLossDiluted

(83)us-gaap_ParticipatingSecuritiesDistributedAndUndistributedEarningsLossDiluted

Income from continuing operations available to common shareholders

$ 32,897lanc_IncomeFromContinuingOperationsAvailableToCommonShareholders

$ 37,082lanc_IncomeFromContinuingOperationsAvailableToCommonShareholders

$ 55,620lanc_IncomeFromContinuingOperationsAvailableToCommonShareholders

$ 61,102lanc_IncomeFromContinuingOperationsAvailableToCommonShareholders

Weighted average common shares outstanding - basic (in shares)

27,294us-gaap_WeightedAverageNumberOfSharesOutstandingBasic

27,244us-gaap_WeightedAverageNumberOfSharesOutstandingBasic

27,290us-gaap_WeightedAverageNumberOfSharesOutstandingBasic

27,256us-gaap_WeightedAverageNumberOfSharesOutstandingBasic

Incremental share effect from:

Nonparticipating restricted stock (in shares)

3us-gaap_IncrementalCommonSharesAttributableToNonvestedSharesWithForfeitableDividends

4us-gaap_IncrementalCommonSharesAttributableToNonvestedSharesWithForfeitableDividends

Stock-settled stock appreciation rights (in shares)

26us-gaap_IncrementalCommonSharesAttributableToShareBasedPaymentArrangements

52us-gaap_IncrementalCommonSharesAttributableToShareBasedPaymentArrangements

25us-gaap_IncrementalCommonSharesAttributableToShareBasedPaymentArrangements

46us-gaap_IncrementalCommonSharesAttributableToShareBasedPaymentArrangements

Weighted average common shares outstanding - diluted (in shares)

27,323us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding

27,299us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding

27,319us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding

27,306us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding

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

$ 1.21us-gaap_IncomeLossFromContinuingOperationsPerBasicShare

$ 1.36us-gaap_IncomeLossFromContinuingOperationsPerBasicShare

$ 2.04us-gaap_IncomeLossFromContinuingOperationsPerBasicShare

$ 2.24us-gaap_IncomeLossFromContinuingOperationsPerBasicShare

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

$ 1.20us-gaap_IncomeLossFromContinuingOperationsPerDilutedShare

$ 1.36us-gaap_IncomeLossFromContinuingOperationsPerDilutedShare

$ 2.04us-gaap_IncomeLossFromContinuingOperationsPerDilutedShare

$ 2.24us-gaap_IncomeLossFromContinuingOperationsPerDilutedShare

- 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 share of common stock or unit outstanding during the reporting period.

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The amount of net income (loss) derived from continuing operations during the period available to each share of common stock or common unit outstanding during the reporting period and to each share or unit that would have been outstanding assuming the issuance of common shares or units for all dilutive potential common shares or units outstanding during the reporting period.

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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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