Commitment and Contingencies - Narratives (Details) - USD ($) $ in Millions	1 Months Ended		6 Months Ended	12 Months Ended
	Oct. 28, 2017	Dec. 31, 2016	Jan. 27, 2018	Jul. 29, 2017	Jul. 30, 2016	Jul. 25, 2015	Oct. 29, 2016
Loss Contingencies [Line Items]
Loss contingency, estimated loss							$ 13.0
Loss contingency accrual, payments		$ 0.1
Operating lease rental			$ 14.4	$ 32.5	$ 26.8	$ 18.5
Machinery rental expense			15.0	26.0	23.0	$ 20.4
Letters of credit outstanding amount			48.6	48.7	57.6
Standby Letters of Credit
Loss Contingencies [Line Items]
Letters of credit outstanding amount			48.6	48.7
Goodman Networks, Inc. Wireline Operations
Loss Contingencies [Line Items]
Escrow deposit			10.0
Funds released from escrow				2.5
Indemnification Portion Subject to Certain Conditions, Not Less Than Twelve Months | Goodman Networks, Inc. Wireline Operations
Loss Contingencies [Line Items]
Escrow deposit			22.5
Indemnification Portion Subject to Seller Satisfaction of Certain Liabilities | Goodman Networks, Inc. Wireline Operations
Loss Contingencies [Line Items]
Escrow deposit				10.0
Performance Guarantee and Surety Bond [Member]
Loss Contingencies [Line Items]
Guarantor obligations, carrying value			$ 118.1	$ 118.2	$ 165.8
S and N
Loss Contingencies [Line Items]
Damages sought	$ 3.8