Segment Information (Details) - USD ($)	3 Months Ended												12 Months Ended
	Jul. 31, 2017	Apr. 30, 2017	Jan. 31, 2017	Oct. 31, 2016	Jul. 31, 2016	Apr. 30, 2016	Jan. 31, 2016	Oct. 31, 2015	Jul. 31, 2015	Apr. 30, 2015	Jan. 31, 2015	Oct. 31, 2014	Jul. 31, 2017	Jul. 31, 2016	Jul. 31, 2015	Feb. 23, 2016
Segment Reporting Information, Profit (Loss)
Net sales	$ 147,762,000	$ 127,792,000	$ 139,028,000	$ 135,786,000	$ 152,377,000	$ 124,187,000	$ 70,323,000	$ 64,117,000	$ 77,463,000	$ 71,633,000	$ 81,802,000	$ 76,391,000	$ 550,368,000	$ 411,004,000	$ 307,289,000
Operating income (loss)													37,042,000	(576,000)	34,077,000
Net income (loss)	7,314,000	$ 4,417,000	$ 6,585,000	$ (2,489,000)	2,702,000	$ (14,355,000)	$ 2,476,000	$ 1,439,000	5,475,000	$ 4,960,000	$ 7,585,000	5,225,000	15,827,000	(7,738,000)	23,245,000
Provision for income taxes													9,654,000	(454,000)	10,758,000
Interest (income) and other expense													(68,000)	(134,000)	(405,000)
Interest expense													11,629,000	7,750,000	479,000
Amortization of stock-based compensation													8,506,000	4,117,000	4,363,000
Amortization of intangibles													22,823,000	13,415,000	6,211,000
Depreciation and amortization of property, plant and equipment													14,354,000	9,830,000	6,525,000
Settlement of intellectual property litigation													(12,020,000)	0	0
Acquisition plan expenses													0	21,276,000	0
Strategic alternatives analysis expenses and other															585,000
Adjusted EBITDA													70,705,000	48,062,000	51,761,000
Purchases of property, plant and equipment													8,150,000	5,667,000	3,362,000
Long-lived assets acquired in connection with the TCS acquisition														455,084,000
Total assets	832,063,000				921,196,000				473,877,000				832,063,000	921,196,000	473,877,000
Secured Credit Facility
Segment Reporting Information, Profit (Loss)
Interest expense related to credit facility													11,106,000	6,933,000
Line of credit facility, maximum borrowing capacity																$ 400,000,000
Committed Secured Revolving Credit Facility
Segment Reporting Information, Profit (Loss)
Interest expense related to credit facility															198,000
Line of credit facility, maximum borrowing capacity												$ 100,000,000
Unallocated
Segment Reporting Information, Profit (Loss)
Net sales													0	0	0
Operating income (loss)													(5,585,000)	(46,837,000)	(16,660,000)
Net income (loss)													(26,465,000)	(53,541,000)	(27,290,000)
Provision for income taxes													9,396,000	(526,000)	10,900,000
Interest (income) and other expense													74,000	(232,000)	(467,000)
Interest expense													11,410,000	7,462,000	198,000
Amortization of stock-based compensation													8,506,000	4,117,000	4,363,000
Amortization of intangibles													0	0	0
Depreciation and amortization of property, plant and equipment													1,478,000	751,000	33,000
Settlement of intellectual property litigation													(12,020,000)
Acquisition plan expenses														21,276,000
Strategic alternatives analysis expenses and other															585,000
Adjusted EBITDA													(7,621,000)	(20,693,000)	(11,678,000)
Purchases of property, plant and equipment													97,000	75,000	66,000
Long-lived assets acquired in connection with the TCS acquisition														4,359,000
Total assets	40,393,000				62,395,000				144,598,000				40,393,000	62,395,000	144,598,000
Commercial Solutions | Operating Segments
Segment Reporting Information, Profit (Loss)
Net sales													330,867,000	248,955,000	203,674,000
Operating income (loss)													33,234,000	23,255,000	20,733,000
Net income (loss)													32,871,000	22,785,000	20,502,000
Provision for income taxes													258,000	72,000	(142,000)
Interest (income) and other expense													(108,000)	109,000	92,000
Interest expense													213,000	289,000	281,000
Amortization of stock-based compensation													0	0	0
Amortization of intangibles													17,698,000	10,592,000	6,211,000
Depreciation and amortization of property, plant and equipment													9,938,000	7,073,000	5,250,000
Settlement of intellectual property litigation													0
Acquisition plan expenses														0
Strategic alternatives analysis expenses and other															0
Adjusted EBITDA													60,870,000	40,920,000	32,194,000
Purchases of property, plant and equipment													7,007,000	4,614,000	2,233,000
Long-lived assets acquired in connection with the TCS acquisition														367,865,000
Total assets	606,436,000				631,936,000				233,965,000				606,436,000	631,936,000	233,965,000
Commercial Solutions | Intersegment Eliminations
Segment Reporting Information, Profit (Loss)
Intersegment sales													12,492,000	6,266,000	6,165,000
Government Solutions | Operating Segments
Segment Reporting Information, Profit (Loss)
Net sales													219,501,000	162,049,000	103,615,000
Operating income (loss)													9,393,000	23,006,000	30,004,000
Net income (loss)													9,421,000	23,018,000	30,033,000
Provision for income taxes													0	0	0
Interest (income) and other expense													(34,000)	(11,000)	(30,000)
Interest expense													6,000	(1,000)	0
Amortization of stock-based compensation													0	0	0
Amortization of intangibles													5,125,000	2,823,000	0
Depreciation and amortization of property, plant and equipment													2,938,000	2,006,000	1,242,000
Settlement of intellectual property litigation													0
Acquisition plan expenses														0
Strategic alternatives analysis expenses and other															0
Adjusted EBITDA													17,456,000	27,835,000	31,245,000
Purchases of property, plant and equipment													1,046,000	978,000	1,063,000
Long-lived assets acquired in connection with the TCS acquisition														82,860,000
Total assets	$ 185,234,000				$ 226,865,000				$ 95,314,000				$ 185,234,000	$ 226,865,000	$ 95,314,000