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Long Term Debt - Additional Information (Detail)						3 Months Ended		6 Months Ended
Long Term Debt - Additional Information (Detail)	Mar. 18, 2015 USD ($) LegalMatter	Mar. 16, 2015	Sep. 27, 2012 USD ($) LegalMatter	Jun. 14, 2012 USD ($) LegalMatter	Oct. 05, 2010 USD ($) LegalMatter	Jun. 30, 2015 USD ($)	Jun. 30, 2014 USD ($)	Jun. 30, 2015 USD ($)	Jun. 30, 2014 USD ($)	Oct. 01, 2015	Jul. 01, 2015	Dec. 31, 2014 USD ($)	Dec. 24, 2012 USD ($)
Debt Instrument [Line Items]
Assets						$ 5,049,528,000		$ 5,049,528,000				$ 5,394,011,000
Letters of credit outstanding						41,300,000		41,300,000
Interest expense related to amortization of debt issuance costs						$ 743,000	$ 547,000	$ 1,300,000	$ 1,100,000
Credit Agreement
Debt Instrument [Line Items]
Aggregate amount by which the revolving credit facility can be increased			$ 100,000,000
Credit facility, maximum borrowing capacity			$ 700,000,000
Debt maturity date			Sep. 27, 2017
Commitment fee payable to the lenders for the unused portion of the credit facility			0.50%
Credit agreement, financial covenant description								The Company must not permit its debt to capitalization ratio to exceed 45%. The Credit Agreement generally defines the debt to capitalization ratio as the ratio of (a) total borrowed money indebtedness to (b) the sum of such indebtedness plus consolidated net worth, with consolidated net worth determined as of the last day of the most recently ended fiscal quarter. The Company also must not permit the interest coverage ratio as of the last day of a fiscal quarter to be less than 3.00 to 1.00. The Credit Agreement generally defines the interest coverage ratio as the ratio of earnings before interest, taxes, depreciation and amortization (“EBITDA”) of the four prior fiscal quarters to interest charges for the same period. The Company was in compliance with these covenants at June 30, 2015
Number of compliance covenants \| LegalMatter			2
Credit Agreement \| Minimum
Debt Instrument [Line Items]
Interest coverage ratio that the Company must exceed on the last day of the fiscal quarter			300.00%
Credit Agreement \| Maximum
Debt Instrument [Line Items]
Debt to capitalization ratio, percentage the Company must not exceed at any time			45.00%
Credit Agreement \| Maximum \| Subsidiaries
Debt Instrument [Line Items]
Assets			$ 1,000,000
Credit Agreement \| London Interbank Offered Rate (LIBOR)
Debt Instrument [Line Items]
Applicable margin						2.75%		2.75%
Credit Agreement \| London Interbank Offered Rate (LIBOR) \| Scenario, Forecast
Debt Instrument [Line Items]
Applicable margin										2.25%
Credit Agreement \| London Interbank Offered Rate (LIBOR) \| Subsequent Event
Debt Instrument [Line Items]
Applicable margin											2.25%
Credit Agreement \| London Interbank Offered Rate (LIBOR) \| Minimum
Debt Instrument [Line Items]
Applicable margin			2.25%
Credit Agreement \| London Interbank Offered Rate (LIBOR) \| Maximum
Debt Instrument [Line Items]
Applicable margin			3.25%
Credit Agreement \| Base Rate
Debt Instrument [Line Items]
Applicable margin						1.75%		1.75%
Credit Agreement \| Base Rate \| Scenario, Forecast
Debt Instrument [Line Items]
Applicable margin										1.25%
Credit Agreement \| Base Rate \| Subsequent Event
Debt Instrument [Line Items]
Applicable margin											1.25%
Credit Agreement \| Base Rate \| Minimum
Debt Instrument [Line Items]
Applicable margin			1.25%
Credit Agreement \| Base Rate \| Maximum
Debt Instrument [Line Items]
Applicable margin			2.25%
Reimbursement Agreement
Debt Instrument [Line Items]
Letters of credit outstanding						$ 41,300,000		$ 41,300,000
Reimbursement Agreement \| London Interbank Offered Rate (LIBOR)
Debt Instrument [Line Items]
Debt Instrument, Basis Spread on Variable Rate		2.25%
2015 Term Loan Agreement
Debt Instrument [Line Items]
Line of credit facility, frequency of payment and payment terms								The Term Loan Borrowing is payable in quarterly principal installments, together with accrued interest, on each June 30, September 30, December 31 and March 31, commencing on June 30, 2015. Each of the first four principal installments is in an amount equal to 2.5% of the Term Loan Borrowing and each successive quarterly installment, until and including June 30, 2017, is in an amount equal to 5.0% of the Term Loan Borrowing, with the outstanding principal balance of the Term Loan Borrowing due on the maturity date under the 2015 Term Loan Agreement. The maturity date under the 2015 Term Loan Agreement is September 27, 2017. Loans under the 2015 Term Loan Agreement bear interest, at the Company’s election, at the per annum rate of LIBOR rate plus 3.25% or base rate plus 2.25%.
Line of credit facility, frequency of payments								Quarterly
Commencement date of principal payments	Jun. 30, 2015
Debt maturity date	Sep. 27, 2017
Credit agreement, financial covenant description								The Company must not permit its debt to capitalization ratio to exceed 45%. The 2015 Term Loan Agreement generally defines the debt to capitalization ratio as the ratio of (a) total borrowed money indebtedness to (b) the sum of such indebtedness plus consolidated net worth, with consolidated net worth determined as of the most recently ended fiscal quarter. The Company also must not permit the interest coverage ratio as of the last day of a fiscal quarter to be less than 3.00 to 1.00. The 2015 Term Loan Agreement generally defines the interest coverage ratio as the ratio of EBITDA of the four prior fiscal quarters to interest charges for the same period. The Company was in compliance with these covenants at June 30, 2015.
Number of compliance covenants \| LegalMatter	2
Line of credit, amount outstanding	$ 200,000,000
Quarterly interest payment, first payment date								June 30
Quarterly interest payment, second payment date								September 30
Quarterly interest payment, third payment date								December 31
Quarterly interest payment, fourth payment date								March 31
2015 Term Loan Agreement \| Subsidiaries
Debt Instrument [Line Items]
Assets	$ 1,000,000
2015 Term Loan Agreement \| Minimum
Debt Instrument [Line Items]
Interest coverage ratio that the Company must exceed on the last day of the fiscal quarter	300.00%
2015 Term Loan Agreement \| Maximum
Debt Instrument [Line Items]
Debt to capitalization ratio, percentage the Company must not exceed at any time	45.00%
Pro forma ratio of debt to EBITDA	250.00%
2015 Term Loan Agreement \| London Interbank Offered Rate (LIBOR)
Debt Instrument [Line Items]
Debt Instrument, Basis Spread on Variable Rate								3.25%
2015 Term Loan Agreement \| Base Rate
Debt Instrument [Line Items]
Debt Instrument, Basis Spread on Variable Rate								2.25%
2015 Term Loan Agreement \| First Four Quarterly Installments
Debt Instrument [Line Items]
Installment amounts percentage of the original principal amount	2.50%
2015 Term Loan Agreement \| Successive Quarterly Installment, Until and Including June 30, 2017
Debt Instrument [Line Items]
Installment amounts percentage of the original principal amount	5.00%
4.97% Series A Senior Notes, Due October 5th 2020
Debt Instrument [Line Items]
Debt maturity date					Oct. 05, 2020
Number of compliance covenants \| LegalMatter					2
Long-term debt, aggregate principal amount					$ 300,000,000
Debt interest rate					4.97%
Semi-annual interest payment, first payment date								April 5
Semi-annual interest payment, second payment date								October 5
Notes issuance date					Oct. 05, 2010
Description of the prepayment terms								Notes are prepayable at the Company’s option, in whole or in part, provided that in the case of a partial prepayment, prepayment must be in an amount not less than 5% of the aggregate principal amount of the notes then outstanding, at any time and from time to time at 100% of the principal amount prepaid, plus accrued and unpaid interest to the prepayment date, plus a “make-whole” premium as specified in the note purchase agreements. The Company must offer to prepay the notes upon the occurrence of any change of control. In addition, the Company must offer to prepay the notes upon the occurrence of certain asset dispositions if the proceeds therefrom are not timely reinvested in productive assets. If any offer to prepay is accepted, the purchase price of each prepaid note is 100% of the principal amount thereof, plus accrued and unpaid interest thereon to the prepayment date.
Description of the acceptance terms								If any offer to prepay is accepted, the purchase price of each prepaid note is 100% of the principal amount thereof, plus accrued and unpaid interest thereon to the prepayment date.
Acceptance terms, percent of principal before accrued and unpaid interest					100.00%
Note purchase agreement, financial covenant description								The Company must not permit its debt to capitalization ratio to exceed 50% at any time. The note purchase agreements generally define the debt to capitalization ratio as the ratio of (a) total borrowed money indebtedness to (b) the sum of such indebtedness plus consolidated net worth, with consolidated net worth determined as of the last day of the most recently ended fiscal quarter. The Company also must not permit the interest coverage ratio as of the last day of a fiscal quarter to be less than 2.50 to 1.00. The note purchase agreements generally define the interest coverage ratio as the ratio of EBITDA for the four prior fiscal quarters to interest charges for that same period. The Company was in compliance with these covenants at June 30, 2015.
4.97% Series A Senior Notes, Due October 5th 2020 \| Minimum
Debt Instrument [Line Items]
Interest coverage ratio that the Company must exceed on the last day of the fiscal quarter					250.00%
Prepayment terms, percent of principal before accrued and unpaid interest and "make-whole" premium					100.00%
4.97% Series A Senior Notes, Due October 5th 2020 \| Maximum
Debt Instrument [Line Items]
Debt to capitalization ratio, percentage the Company must not exceed at any time					50.00%
4.27% Series B Senior Notes, Due June 14th 2022
Debt Instrument [Line Items]
Debt maturity date				Jun. 14, 2022
Number of compliance covenants \| LegalMatter				2
Long-term debt, aggregate principal amount				$ 300,000,000
Debt interest rate				4.27%
Semi-annual interest payment, first payment date								April 5
Semi-annual interest payment, second payment date								October 5
Notes issuance date				Jun. 14, 2012
Description of the prepayment terms								Notes are prepayable at the Company’s option, in whole or in part, provided that in the case of a partial prepayment, prepayment must be in an amount not less than 5% of the aggregate principal amount of the notes then outstanding, at any time and from time to time at 100% of the principal amount prepaid, plus accrued and unpaid interest to the prepayment date, plus a “make-whole” premium as specified in the note purchase agreements. The Company must offer to prepay the notes upon the occurrence of any change of control. In addition, the Company must offer to prepay the notes upon the occurrence of certain asset dispositions if the proceeds therefrom are not timely reinvested in productive assets. If any offer to prepay is accepted, the purchase price of each prepaid note is 100% of the principal amount thereof, plus accrued and unpaid interest thereon to the prepayment date.
Description of the acceptance terms								If any offer to prepay is accepted, the purchase price of each prepaid note is 100% of the principal amount thereof, plus accrued and unpaid interest thereon to the prepayment date.
Acceptance terms, percent of principal before accrued and unpaid interest				100.00%
Note purchase agreement, financial covenant description								The Company must not permit its debt to capitalization ratio to exceed 50% at any time. The note purchase agreements generally define the debt to capitalization ratio as the ratio of (a) total borrowed money indebtedness to (b) the sum of such indebtedness plus consolidated net worth, with consolidated net worth determined as of the last day of the most recently ended fiscal quarter. The Company also must not permit the interest coverage ratio as of the last day of a fiscal quarter to be less than 2.50 to 1.00. The note purchase agreements generally define the interest coverage ratio as the ratio of EBITDA for the four prior fiscal quarters to interest charges for that same period. The Company was in compliance with these covenants at June 30, 2015.
4.27% Series B Senior Notes, Due June 14th 2022 \| Minimum
Debt Instrument [Line Items]
Interest coverage ratio that the Company must exceed on the last day of the fiscal quarter				250.00%
Prepayment terms, percent of principal before accrued and unpaid interest and "make-whole" premium				100.00%
4.27% Series B Senior Notes, Due June 14th 2022 \| Maximum
Debt Instrument [Line Items]
Debt to capitalization ratio, percentage the Company must not exceed at any time				50.00%
Reimbursement Agreement and 2015 Term Loan Agreement
Debt Instrument [Line Items]
Debt issuance costs								$ 2,000,000
Revolving Credit Facility
Debt Instrument [Line Items]
Line of credit, amount outstanding						0		0
Line of credit, available borrowing capacity						500,000,000		500,000,000
Revolving Credit Facility \| Credit Agreement
Debt Instrument [Line Items]
Current aggregate borrowing capacity			$ 500,000,000
Revolving Credit Facility \| Letter of Credit \| Credit Agreement
Debt Instrument [Line Items]
Current aggregate borrowing capacity			150,000,000
Revolving Credit Facility \| Swing Line Facility \| Credit Agreement
Debt Instrument [Line Items]
Current aggregate borrowing capacity			$ 40,000,000
Term Loan Facility
Debt Instrument [Line Items]
Line of credit, amount outstanding						$ 77,500,000		$ 77,500,000
Line of credit facility, interest rate						3.125%		3.125%
Term Loan Facility \| Credit Agreement
Debt Instrument [Line Items]
Current aggregate borrowing capacity													$ 100,000,000
Line of credit facility, frequency of payment and payment terms								The term loan facility is payable in quarterly principal installments, which commenced December 27, 2012. The installment amounts vary from 1.25% of the original principal amount for each of the first four quarterly installments, 2.50% of the original principal amount for each of the subsequent eight quarterly installments, 5.00% of the original principal amount for the subsequent four quarterly installments and 13.75% of the original principal amount for the final four quarterly installments.
Line of credit facility, frequency of payments								Quarterly
Commencement date of principal payments			Dec. 27, 2012
Term Loan Facility \| Credit Agreement \| First Four Quarterly Installments
Debt Instrument [Line Items]
Installment amounts percentage of the original principal amount			1.25%
Term Loan Facility \| Credit Agreement \| Subsequent Eight Quarterly Installments
Debt Instrument [Line Items]
Installment amounts percentage of the original principal amount			2.50%
Term Loan Facility \| Credit Agreement \| Subsequent Four Quarterly Installments
Debt Instrument [Line Items]
Installment amounts percentage of the original principal amount			5.00%
Term Loan Facility \| Credit Agreement \| Amount For The Final Four Quarterly Installments
Debt Instrument [Line Items]
Installment amounts percentage of the original principal amount			13.75%