Pension plan (Details Textuals) (USD $) In Millions, unless otherwise specified	3 Months Ended	6 Months Ended
Dec. 27, 2014	Dec. 27, 2014
Compensation and Retirement Disclosure [Abstract]
Defined benefit plans, estimated future employer contributions each remaining quarter of current fiscal year	$ 10.0
Company's contribution to pension plan in the current quarter		$ 20.0
Company's estimated future employer contributions in current fiscal year	The Company expects to make an additional contribution to the Plan of $10.0 million in each of the remaining quarters of the fiscal year.

Descriptive information regarding the employer's best estimate, as soon as it can be reasonably determined, of contributions expected to be paid in the current remaining fiscal period. Estimated contributions may be presented in the aggregate combining (1) contributions required by funding regulations or laws, (2) discretionary contributions, and (3) noncash contributions. Description may include a range of expected contributions, required minimum contribution, whether the expected contribution is discretionary, and further explanation.

No definition available.

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