Acquisitions - Narrative (Details) - USD ($)						3 Months Ended		6 Months Ended
	Sep. 27, 2019	Sep. 23, 2019	Apr. 18, 2019	Jan. 29, 2019	Jul. 31, 2018	Dec. 27, 2019	Dec. 31, 2018	Dec. 27, 2019	Dec. 31, 2018	Jun. 30, 2019	Jan. 31, 2019
Business Acquisition [Line Items]
Estimated goodwill						$ 614,648,000		$ 614,648,000		$ 562,146,000
Revenues						193,913,000	$ 159,089,000	371,217,000	$ 303,145,000
Income before income taxes						20,786,000	$ 16,866,000	38,015,000	$ 27,474,000
The Athena Group, Inc. [Member]
Business Acquisition [Line Items]
Payments to Acquire Business Three, Net of Cash Acquired			$ 34,000,000
Cash paid at closing			$ 34,049,000
Useful life of acquired assets			11 years
Estimated goodwill			$ 15,999,000
Estimated fair value of assets acquired			33,603,000
The Athena Group, Inc. [Member] | Developed Technology Rights
Business Acquisition [Line Items]
Finite-lived intangible assets acquired			23,700,000
American Panel Corporation
Business Acquisition [Line Items]
Payments to Acquire Business Three, Net of Cash Acquired		$ 100,000,000
Cash paid at closing		100,826,000
Estimated goodwill		52,255,000
Amortization period for tax purposes	15 years
Tax deductible goodwill		52,357,000
Estimated fair value of assets acquired		$ 97,328,000
Revenues						9,653		10,596
Income before income taxes						1,495		1,802
American Panel Corporation | Customer Relationships
Business Acquisition [Line Items]
Finite-lived intangible assets acquired	$ 20,400,000
Useful life of acquired assets	11 years
American Panel Corporation | Developed Technology Rights
Business Acquisition [Line Items]
Finite-lived intangible assets acquired	$ 10,400,000
Useful life of acquired assets	11 years
American Panel Corporation | Backlog
Business Acquisition [Line Items]
Finite-lived intangible assets acquired	$ 2,400,000
Useful life of acquired assets	2 years
Syntonic Microwave LLC
Business Acquisition [Line Items]
Payments to Acquire Business Three, Net of Cash Acquired			12,000,000
Cash paid at closing			$ 13,118,000
Useful life of acquired assets			15 years
Estimated goodwill			$ 4,232,000
Estimated fair value of assets acquired			13,118,000
Syntonic Microwave LLC | Customer Relationships
Business Acquisition [Line Items]
Finite-lived intangible assets acquired			$ 4,200,000
Useful life of acquired assets			10 years
Syntonic Microwave LLC | Developed Technology Rights
Business Acquisition [Line Items]
Finite-lived intangible assets acquired			$ 2,500,000
Useful life of acquired assets			9 years
Syntonic Microwave LLC | Backlog
Business Acquisition [Line Items]
Finite-lived intangible assets acquired			$ 400,000
Useful life of acquired assets			1 year
GECO Avionics, LLC
Business Acquisition [Line Items]
Cash paid at closing				$ 36,500,000
Estimated goodwill											$ 21,023,000
Tax deductible goodwill						20,300,000		20,300,000
Estimated fair value of assets acquired											$ 36,500,000
GECO Avionics, LLC | Customer Relationships
Business Acquisition [Line Items]
Finite-lived intangible assets acquired				$ 6,900,000
Useful life of acquired assets				11 years
GECO Avionics, LLC | Developed Technology Rights
Business Acquisition [Line Items]
Finite-lived intangible assets acquired				$ 4,800,000
Useful life of acquired assets				10 years
GECO Avionics, LLC | Backlog
Business Acquisition [Line Items]
Finite-lived intangible assets acquired				$ 1,000,000
Germane Systems
Business Acquisition [Line Items]
Cash paid at closing					$ 47,166,000
Total purchase price					45,000,000,000			1,244,000
Estimated goodwill					23,558,000
Tax deductible goodwill						$ 21,763,000		$ 21,763,000
Estimated fair value of assets acquired					45,922,000
Germane Systems | Customer Relationships
Business Acquisition [Line Items]
Finite-lived intangible assets acquired					$ 8,500,000,000
Useful life of acquired assets					11 years
Germane Systems | Developed Technology Rights
Business Acquisition [Line Items]
Finite-lived intangible assets acquired					$ 4,200,000,000
Useful life of acquired assets					8 years
Germane Systems | Backlog
Business Acquisition [Line Items]
Finite-lived intangible assets acquired					$ 210,000,000
Useful life of acquired assets					1 year