v3.3.1.900

Summary of Significant Accounting Policies - Summary of Property, Plant, and Equipment (Detail)	12 Months Ended
	Jan. 02, 2016
Land Improvements [Member]
Depreciation Amortization Impairment [Line Items]
Estimated useful life of property, plant and equipment	10 years
Buildings [Member]
Depreciation Amortization Impairment [Line Items]
Estimated useful life of property, plant and equipment	40 years
Minimum [Member]
Depreciation Amortization Impairment [Line Items]
Estimated useful life of property, plant and equipment	5 years
Minimum [Member] | Machinery and Equipment [Member]
Depreciation Amortization Impairment [Line Items]
Estimated useful life of property, plant and equipment	5 years
Minimum [Member] | Furniture and Fixtures [Member]
Depreciation Amortization Impairment [Line Items]
Estimated useful life of property, plant and equipment	5 years
Maximum [Member]
Depreciation Amortization Impairment [Line Items]
Estimated useful life of property, plant and equipment	40 years
Maximum [Member] | Machinery and Equipment [Member]
Depreciation Amortization Impairment [Line Items]
Estimated useful life of property, plant and equipment	10 years
Maximum [Member] | Furniture and Fixtures [Member]
Depreciation Amortization Impairment [Line Items]
Estimated useful life of property, plant and equipment	10 years

X

- Definition

Depreciation Amortization Impairment [Line Items]

+ References

No definition available.

+ Details

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Namespace Prefix:	dvly_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

X

- Definition

Useful life of long lived, physical assets used in the normal conduct of business and not intended for resale, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Examples include, but not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

X

- Details

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Namespace Prefix:
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Balance Type:
Period Type:

X

- Details

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Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

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Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

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Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

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Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

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Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: