GOODWILL: (Details) $ in Thousands	9 Months Ended
Dec. 31, 2017 USD ($)
Goodwill
Goodwill at the beginning of year	$ 592,731
Arbor adjustment	(21)
Change in foreign currency translation adjustment	117
Goodwill at the end of year	592,827
U.S.
Goodwill
Goodwill at the end of year	581,170
APAC
Goodwill
Goodwill at the end of year	11,657
Marketing Services
Goodwill
Goodwill at the beginning of year	118,890
Arbor adjustment	0
Change in foreign currency translation adjustment	82
Goodwill at the end of year	118,972
Marketing Services \| U.S.
Goodwill
Goodwill at the end of year	110,910
Marketing Services \| APAC
Goodwill
Goodwill at the end of year	8,062
Audience Solutions
Goodwill
Goodwill at the beginning of year	273,448
Arbor adjustment	0
Change in foreign currency translation adjustment	0
Goodwill at the end of year	273,448
Audience Solutions \| U.S.
Goodwill
Goodwill at the end of year	273,448
Audience Solutions \| APAC
Goodwill
Goodwill at the end of year	0
Connectivity
Goodwill
Goodwill at the beginning of year	200,393
Arbor adjustment	(21)
Change in foreign currency translation adjustment	35
Goodwill at the end of year	200,407
Connectivity \| U.S.
Goodwill
Goodwill at the end of year	196,812
Connectivity \| APAC
Goodwill
Goodwill at the end of year	$ 3,595

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13816-109267

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6388280&loc=d3e13770-109266

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 45
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=77989000&loc=SL49117168-202975

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Amount of foreign currency translation gain (loss) which increases (decreases) an asset representing future economic benefits from other assets acquired in a business combination that are not individually identified and separately recognized.

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