SUMMARY OF ACCOUNTING POLICIES - Other Information (Details) - USD ($) $ in Thousands	12 Months Ended
	Mar. 31, 2017	Mar. 31, 2016	Mar. 31, 2015
Other Current Assets / Liabilities
Equity investments in non-majority owned companies	$ 200,100	$ 122,900
Customer working capital advances and accruals included in other current liabilities	231,300	253,700
Deferred revenue	280,700	332,300
Customer-related third party banking institution equipment financing net settlement	90,576	0	$ 0
Other acquisitions
Other Current Assets / Liabilities
Assets financed by a third party banking institution included in other current assets		83,600
Other current liability for purchase of assets on behalf of customer financed by a third party banking institution		122,000
Customer Related Accruals
Other Current Assets / Liabilities
Customer working capital advances and accruals included in other current liabilities	501,900	479,500
Asset-Backed Securitization Programs
Other Current Assets / Liabilities
Other current assets	506,522	$ 501,097	$ 600,672
RIB Software AG | YTWO Formative Joint Venture
Other Current Assets / Liabilities
Payments to acquire interest in joint venture	$ 60,000