Fair Value of Financial Instruments (Narrative) (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2017	Dec. 31, 2016	Sep. 30, 2017	Jun. 30, 2017	Sep. 30, 2016	Jun. 30, 2016
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Current portion of contingent consideration	$ 38,629		$ 38,629			$ 30,675
Fair Value, Inputs, Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Gain (loss) due to change in fair value of contingent consideration	(6,913)		(23,794)
Fair value of liability for contingent consideration	97,031		97,031		$ 103,493	114,036
Barcode, Networking & Security Segment [Member] | Fair Value, Inputs, Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Gain (loss) due to change in fair value of contingent consideration	0		(69)
Fair value of liability for contingent consideration	0		0		13,167	0
Barcode, Networking & Security Segment [Member] | POS Portal [Member] | Fair Value, Inputs, Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Gain (loss) due to change in fair value of contingent consideration			(100)
Communications & Services Segment [Member] | Fair Value, Inputs, Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Gain (loss) due to change in fair value of contingent consideration	(6,913)	$ (1,791)	(23,725)	$ (1,961)
Fair value of liability for contingent consideration	97,031	110,880	97,031	110,880	$ 90,326	$ 114,036	$ 110,835	$ 24,652
Communications & Services Segment [Member] | Intelisys [Member] | Fair Value, Inputs, Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Gain (loss) due to change in fair value of contingent consideration	(5,100)	(2,300)	(9,200)	(3,200)
Fair value of liability for contingent consideration	90,700	98,200	90,700	98,200
Current portion of contingent consideration	32,300	25,500	32,300	25,500
Contingent consideration arrangements, maximum range of outcome	115,200		115,200
Communications & Services Segment [Member] | Network1 [Member] | Fair Value, Inputs, Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Gain (loss) due to change in fair value of contingent consideration	(1,800)	(200)	(14,500)	100
Fair value of liability for contingent consideration	6,300	12,700	6,300	12,700
Current portion of contingent consideration	6,300	7,300	6,300	7,300
Contingent consideration arrangements, maximum range of outcome	$ 7,100		$ 7,100
Communications & Services Segment [Member] | Imago [Member] | Fair Value, Inputs, Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Gain (loss) due to change in fair value of contingent consideration		$ 800		$ 1,100