Goodwill impairment charges.

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- Definition

Impairment charges.

+ References

No definition available.

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- Definition

Amount of write-down of assets recognized in the income statement. Includes, but is not limited to, losses from tangible assets, intangible assets and goodwill.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 360
-SubTopic 10
-Section 45
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=68055307&loc=d3e2420-110228

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-Publisher FASB
-Name Accounting Standards Codification
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-Section 45
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-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3602-108585

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- Definition

Amount of increase (decrease) in the value of a contingent consideration liability, including, but not limited to, differences arising upon settlement.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 50
-Paragraph 4
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=35744584&loc=d3e7008-128479

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- Definition

Amount of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. Excludes cash and cash equivalents within disposal group and discontinued operation.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
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-Paragraph 1
-Subparagraph (a)
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-Section S99
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Cash includes currency on hand as well as demand deposits with banks or financial institutions. It also includes other kinds of accounts that have the general characteristics of demand deposits in that the customer may deposit additional funds at any time and effectively may withdraw funds at any time without prior notice or penalty. Cash equivalents, excluding items classified as marketable securities, include short-term, highly liquid Investments that are both readily convertible to known amounts of cash, and so near their maturity that they present minimal risk of changes in value because of changes in interest rates. Generally, only investments with original maturities of three months or less qualify under that definition. Original maturity means original maturity to the entity holding the investment. For example, both a three-month US Treasury bill and a three-year Treasury note purchased three months from maturity qualify as cash equivalents. However, a Treasury note purchased three years ago does not become a cash equivalent when its remaining maturity is three months. Short-term investments, exclusive of cash equivalents, generally consist of marketable securities intended to be sold within one year (or the normal operating cycle if longer) and may include trading securities, available-for-sale securities, or held-to-maturity securities (if maturing within one year), as applicable.

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- Definition

The amount of impairment loss recognized in the period resulting from the write-down of the carrying amount of a finite-lived intangible asset to fair value.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
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- Definition

Amount of expenses associated with exit or disposal activities pursuant to an authorized plan. Excludes expenses related to a discontinued operation or an asset retirement obligation.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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Reportable Segment Information (Parenthetical) (Detail) - USD ($)	3 Months Ended			12 Months Ended
	Jul. 31, 2017	Apr. 30, 2017	Jan. 31, 2017	Jul. 31, 2017	Jul. 31, 2016	Jul. 31, 2015	Jul. 31, 2014
Segment Reporting Information [Line Items]
Restructuring Charge				$ 7,167,000	$ 9,641,000	$ (354,000)
Asset impairment charges	$ 1,000,000			84,510,000	0	0
Change in fair value of contingent consideration				(10,239,000)	141,000	(62,000)
Cash and cash equivalents	129,298,000			129,298,000	118,697,000	123,800,000	$ 114,540,000
Corporate
Segment Reporting Information [Line Items]
Cash, cash equivalents and marketable securities	$ 135,200,000			135,200,000
Cash and cash equivalents					97,300,000
Oncura
Segment Reporting Information [Line Items]
Goodwill impairment charges				16,400,000
Change in fair value of contingent consideration				(10,200,000)	100,000
PocketSonics
Segment Reporting Information [Line Items]
Change in fair value of contingent consideration		$ 0		0
Medical Imaging
Segment Reporting Information [Line Items]
Restructuring Charge				1,400,000	6,000,000	(200,000)
Ultrasound
Segment Reporting Information [Line Items]
Restructuring Charge				5,500,000	1,900,000	(100,000)
Goodwill impairment charges				55,200,000
Asset impairment charges				200,000
Ultrasound \| Oncura
Segment Reporting Information [Line Items]
Goodwill impairment charges				16,400,000
Intangible assets impairment charge		3,200,000
Change in fair value of contingent consideration				(10,200,000)
Ultrasound \| Technology \| PocketSonics
Segment Reporting Information [Line Items]
Intangible assets impairment charge		8,100,000		8,100,000
Ultrasound \| Customer relationships \| Oncura
Segment Reporting Information [Line Items]
Intangible assets impairment charge		2,400,000		2,400,000
Ultrasound \| Trade names \| Oncura
Segment Reporting Information [Line Items]
Intangible assets impairment charge		$ 800,000		800,000
BK Medical System
Segment Reporting Information [Line Items]
Impairment charges					10,100,000	1,000,000
Security and Detection
Segment Reporting Information [Line Items]
Restructuring Charge				300,000	$ 1,700,000	$ (100,000)
Asset impairment charges				800,000
Security and Detection \| Pathfinder Therapeutics Inc
Segment Reporting Information [Line Items]
Intangible assets impairment charge			$ 600,000
Security and Detection \| Trade names \| Pathfinder Therapeutics Inc
Segment Reporting Information [Line Items]
Intangible assets impairment charge			100,000	100,000
Security and Detection \| Developed technologies \| Pathfinder Therapeutics Inc
Segment Reporting Information [Line Items]
Intangible assets impairment charge			$ 500,000	$ 500,000