Equity and Other Comprehensive Income (Loss) - Schedule of Changes in Accumulated Other Comprehensive Loss, Net of Tax (Details) - USD ($)
$ in Millions

9 Months Ended

Jun. 30, 2018

Jun. 30, 2017

Accumulated Other Comprehensive Income (Loss) [Line Items]

Balance at beginning of period

^[1]

$ (457.3)

$ (626.4)

Other comprehensive (loss) income before reclassifications

^[1]

(227.6)

24.0

Amounts reclassified from accumulated other comprehensive loss (income)

^[1]

10.6

29.3

Sale of HH&B

^[1]

29.7

Net current period other comprehensive income (loss)

^[1]

(217.0)

83.0

Balance at end of period

^[1]

(674.3)

(543.4)

Accumulated Net Gain (Loss) from Designated or Qualifying Cash Flow Hedges [Member]

Accumulated Other Comprehensive Income (Loss) [Line Items]

Balance at beginning of period

^[1]

(0.7)

(0.2)

Other comprehensive (loss) income before reclassifications

^[1]

0.0

(0.4)

Amounts reclassified from accumulated other comprehensive loss (income)

^[1]

0.5

(0.1)

Sale of HH&B

^[1]

0.0

Net current period other comprehensive income (loss)

^[1]

0.5

(0.5)

Balance at end of period

^[1]

(0.2)

(0.7)

Accumulated Defined Benefit Plans Adjustment [Member]

Accumulated Other Comprehensive Income (Loss) [Line Items]

Balance at beginning of period

^[1]

(462.5)

(523.8)

Other comprehensive (loss) income before reclassifications

^[1]

(3.1)

19.7

Amounts reclassified from accumulated other comprehensive loss (income)

^[1]

11.6

29.4

Sale of HH&B

^[1]

2.9

Net current period other comprehensive income (loss)

^[1]

8.5

52.0

Balance at end of period

^[1]

(454.0)

(471.8)

Accumulated Translation Adjustment [Member]

Accumulated Other Comprehensive Income (Loss) [Line Items]

Balance at beginning of period

^[1]

5.2

(102.4)

Other comprehensive (loss) income before reclassifications

^[1]

(225.3)

4.7

Amounts reclassified from accumulated other comprehensive loss (income)

^[1]

0.0

Sale of HH&B

^[1]

26.8

Net current period other comprehensive income (loss)

^[1]

(225.3)

31.5

Balance at end of period

^[1]

(220.1)

$ (70.9)

Accumulated Net Investment Gain (Loss) Attributable to Parent [Member]

Accumulated Other Comprehensive Income (Loss) [Line Items]

Balance at beginning of period

^[1]

0.7

Other comprehensive (loss) income before reclassifications

^[1]

0.8

Amounts reclassified from accumulated other comprehensive loss (income)

^[1]

(1.5)

Net current period other comprehensive income (loss)

^[1]

(0.7)

Balance at end of period

^[1]

$ 0.0

[1]	All amounts are net of tax and noncontrolling interests.

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