Acquisitions - Schedule of Assets Acquired and Liabilities Assumed (Details) - USD ($) $ in Thousands	Aug. 31, 2016	May 31, 2016	Aug. 01, 2015
Assets:
Goodwill	$ 1,298,375	$ 1,291,593
Liabilities:
Total consideration			$ 134,000
ZEE
Assets:
Cash and cash equivalents			333
Accounts receivable			16,705
Inventory			5,987
Other current assets			1,443
Property, plant and equipment			849
Goodwill			87,442
Liabilities:
Accounts payable			(7,195)
Accrued liabilities			(4,428)
Deferred income taxes			(5,636)
Service contracts | ZEE
Assets:
Intangible assets			34,000
Other intangibles | ZEE
Assets:
Intangible assets			$ 4,500