ACCUMULATED OTHER COMPREHENSIVE INCOME (LOSS), Schedule of Accumulated Other Comprehensive (Loss) Income (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Mar. 31, 2016	Mar. 31, 2015	Mar. 31, 2016	Mar. 31, 2015
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Accumulated other comprehensive (loss) income as of the beginning of the period			$ 4,522,031
Net other comprehensive income (loss) for the period, net of tax	$ 344	$ (14,443)	(9,797)	$ (20,907)
Accumulated other comprehensive income (loss) as of the end of the period	4,635,290		4,635,290
Available for sale securities
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Accumulated other comprehensive (loss) income as of the beginning of the period	(5,371)	4,721	1,420	4,745
Other comprehensive income (loss) before reclassifications and taxes	1,740	3,801	(9,112)	3,745
Amounts reclassified from accumulated other comprehensive income (loss), before tax	53	(2)	53	(2)
Pre-tax net other comprehensive income (loss)	1,793	3,799	(9,059)	3,743
Income tax effect	(694)	(1,462)	3,367	(1,430)
Net other comprehensive income (loss) for the period, net of tax	1,099	2,337	(5,692)	2,313
Accumulated other comprehensive income (loss) as of the end of the period	(4,272)	7,058	(4,272)	7,058
Net investment hedges
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Accumulated other comprehensive (loss) income as of the beginning of the period	105,440	45,930	93,203	32,872
Other comprehensive income (loss) before reclassifications and taxes	(37,416)	48,815	(17,860)	69,701
Amounts reclassified from accumulated other comprehensive income (loss), before tax	0	0	0	0
Pre-tax net other comprehensive income (loss)	(37,416)	48,815	(17,860)	69,701
Income tax effect	14,005	(18,296)	6,686	(26,124)
Net other comprehensive income (loss) for the period, net of tax	(23,411)	30,519	(11,174)	43,577
Accumulated other comprehensive income (loss) as of the end of the period	82,029	76,449	82,029	76,449
Currency translations
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Accumulated other comprehensive (loss) income as of the beginning of the period	(149,328)	(59,003)	(130,476)	(39,505)
Other comprehensive income (loss) before reclassifications and taxes	36,031	(48,374)	16,154	(68,968)
Amounts reclassified from accumulated other comprehensive income (loss), before tax	0	0	0	0
Pre-tax net other comprehensive income (loss)	36,031	(48,374)	16,154	(68,968)
Income tax effect	(1,906)	2,576	(881)	3,672
Net other comprehensive income (loss) for the period, net of tax	34,125	(45,798)	15,273	(65,296)
Accumulated other comprehensive income (loss) as of the end of the period	(115,203)	(104,801)	(115,203)	(104,801)
Sub-total: currency translations and net investment hedges
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Accumulated other comprehensive (loss) income as of the beginning of the period	(43,888)	(13,073)	(37,273)	(6,633)
Other comprehensive income (loss) before reclassifications and taxes	(1,385)	441	(1,706)	733
Amounts reclassified from accumulated other comprehensive income (loss), before tax	0	0	0	0
Pre-tax net other comprehensive income (loss)	(1,385)	441	(1,706)	733
Income tax effect	12,099	(15,720)	5,805	(22,452)
Net other comprehensive income (loss) for the period, net of tax	10,714	(15,279)	4,099	(21,719)
Accumulated other comprehensive income (loss) as of the end of the period	(33,174)	(28,352)	(33,174)	(28,352)
Cash flow hedges
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Accumulated other comprehensive (loss) income as of the beginning of the period	(1,385)	0	(4,650)	0
Other comprehensive income (loss) before reclassifications and taxes	(20,029)	(2,481)	(16,171)	(2,481)
Amounts reclassified from accumulated other comprehensive income (loss), before tax	1,531	60	2,939	60
Pre-tax net other comprehensive income (loss)	(18,498)	(2,421)	(13,232)	(2,421)
Income tax effect	7,029	920	5,028	920
Net other comprehensive income (loss) for the period, net of tax	(11,469)	(1,501)	(8,204)	(1,501)
Accumulated other comprehensive income (loss) as of the end of the period	(12,854)	(1,501)	(12,854)	(1,501)
Accumulated other comprehensive loss
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Accumulated other comprehensive (loss) income as of the beginning of the period	(50,644)	(8,352)	(40,503)	(1,888)
Other comprehensive income (loss) before reclassifications and taxes	(19,674)	1,761	(26,989)	1,997
Amounts reclassified from accumulated other comprehensive income (loss), before tax	1,584	58	2,992	58
Pre-tax net other comprehensive income (loss)	(18,090)	1,819	(23,997)	2,055
Income tax effect	18,434	(16,262)	14,200	(22,962)
Net other comprehensive income (loss) for the period, net of tax	344	(14,443)	(9,797)	(20,907)
Accumulated other comprehensive income (loss) as of the end of the period	$ (50,300)	$ (22,795)	$ (50,300)	$ (22,795)