Employee Retirement and Profit Sharing Plans - Information Regarding Participation in Multiemployer Pension Plans (Details) - Agreement	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017
Western Conference of Teamsters Pension Plan
Defined Benefit Plan Disclosure [Line Items]
Employer Identification Number	916145047
Pension Plan Number	001
PPA Zone Status	Green	Green
FIP / RP Status Pending/ Implemented	NA
Extended Amortization Provisions	No
Expiration Date of Associated Collective Bargaining Agreement(s), First	Jan. 01, 2018
Expiration Date of Associated Collective Bargaining Agreement(s), Last	Aug. 31, 2020
Collective bargaining agreements	13
Percentage of agreements representing total employee participants (as a percent)	29.00%
Central States Southeast And Southwest Areas Pension Plan
Defined Benefit Plan Disclosure [Line Items]
Employer Identification Number	366044243
Pension Plan Number	001
PPA Zone Status	Red	Red
FIP / RP Status Pending/ Implemented	Implemented
Extended Amortization Provisions	No
Expiration Date of Associated Collective Bargaining Agreement(s), First	Feb. 18, 2018
Expiration Date of Associated Collective Bargaining Agreement(s), Last	Aug. 31, 2020
Collective bargaining agreements	19
Retail Wholesale Department Store International Union And Industry Pension Fund
Defined Benefit Plan Disclosure [Line Items]
Employer Identification Number	630708442
Pension Plan Number	001
PPA Zone Status	Red	Green
FIP / RP Status Pending/ Implemented	Implemented
Extended Amortization Provisions	Yes
Expiration Date of Associated Collective Bargaining Agreement(s), First	Jun. 07, 2018
Expiration Date of Associated Collective Bargaining Agreement(s), Last	Oct. 03, 2020
Collective bargaining agreements	8
Dairy Industry Union Pension Plan For Philadelphia Vicinity
Defined Benefit Plan Disclosure [Line Items]
Employer Identification Number	236283288
Pension Plan Number	001
PPA Zone Status	Red	Yellow
FIP / RP Status Pending/ Implemented	Implemented
Extended Amortization Provisions	Yes
Expiration Date of Associated Collective Bargaining Agreement(s), First	Mar. 31, 2018
Expiration Date of Associated Collective Bargaining Agreement(s), Last	Oct. 31, 2020
Collective bargaining agreements	5
Agreements Expiring in 2018 \| Central States Southeast And Southwest Areas Pension Plan
Defined Benefit Plan Disclosure [Line Items]
Percentage of agreements representing total employee participants (as a percent)	40.00%
Agreements Expiring in 2018 \| Retail Wholesale Department Store International Union And Industry Pension Fund
Defined Benefit Plan Disclosure [Line Items]
Percentage of agreements representing total employee participants (as a percent)	2.00%
Agreements Expiring in 2019 \| Central States Southeast And Southwest Areas Pension Plan
Defined Benefit Plan Disclosure [Line Items]
Percentage of agreements representing total employee participants (as a percent)	34.00%
Agreements Expiring in 2019 \| Retail Wholesale Department Store International Union And Industry Pension Fund
Defined Benefit Plan Disclosure [Line Items]
Percentage of agreements representing total employee participants (as a percent)	44.00%
Agreements Expiring in 2020 \| Central States Southeast And Southwest Areas Pension Plan
Defined Benefit Plan Disclosure [Line Items]
Percentage of agreements representing total employee participants (as a percent)	26.00%
Agreements Expiring in 2020 \| Retail Wholesale Department Store International Union And Industry Pension Fund
Defined Benefit Plan Disclosure [Line Items]
Percentage of agreements representing total employee participants (as a percent)	54.00%
Maximum \| Dairy Industry Union Pension Plan For Philadelphia Vicinity
Defined Benefit Plan Disclosure [Line Items]
Percentage of agreements representing total employee participants (as a percent)	62.00%

The Tax Identification Number (TIN), also known as an Employer Identification Number (EIN), is a unique 9-digit value assigned by the IRS.

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-Name Regulation 12B
-Number 240
-Section 12
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Multiemployer Plans Extended Amortization Provisions

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Number Of Collective Bargaining Agreements

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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.

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Three digit plan number for a pension or postretirement benefit plan to which two or more unrelated employers contribute where assets contributed by one participating employer may be used to provide benefits to employees of other participating employers.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 80
-Section 50
-Paragraph 5
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Indicate the multiemployer plan's certified zone status as currently required by the Pension Protection Act of 2006 or a subsequent amendment thereof. The zone status categories are red (critical status), orange (seriously endangered), yellow (endangered), and green (none of the above). The acceptable values are "red", "orange", "yellow", "green", "other", and "NA". A multiemployer plan is a pension or postretirement benefit plan to which two or more unrelated employers contribute where assets contributed by one participating employer may be used to provide benefits to employees of other participating employers.

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Expiration date of the collective bargaining arrangement requiring contributions to the multiemployer plan that will expire first in a group of associated collective bargaining arrangements, in CCYY-MM-DD format. A multiemployer plan is a pension or postretirement benefit plan to which two or more unrelated employers contribute where assets contributed by one participating employer may be used to provide benefits to employees of other participating employers.

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-SubTopic 80
-Section 50
-Paragraph 5
-Subparagraph (d)
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Expiration date of the collective bargaining arrangement requiring contributions to the multiemployer plan that will expire last in a group of associated collective bargaining arrangements, in CCYY-MM-DD format. A multiemployer plan is a pension or postretirement benefit plan to which two or more unrelated employers contribute where assets contributed by one participating employer may be used to provide benefits to employees of other participating employers.

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Percentage of employee participants subject to a collective bargaining arrangement to all of the employer's participants in a pension or postretirement benefit plan to which two or more unrelated employers contribute where assets contributed by one participating employer may be used to provide benefits to employees of other participating employers.

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Indicate whether a funding improvement plan or rehabilitation plan has been implemented or is pending for a pension or postretirement benefit plan to which two or more unrelated employers contribute where assets contributed by one participating employer may be used to provide benefits to employees of other participating employers. The acceptable values are "no", "pending", "implemented", "other", and "NA".

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-SubTopic 80
-Section 50
-Paragraph 5
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