Employee contributions to stock compensation plans.

No definition available.

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- Definition

Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SAB Topic 14.F)
-URI http://asc.fasb.org/extlink&oid=27013229&loc=d3e301413-122809

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5047-113901

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (h)(1)(i)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

+ Details

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- Definition

The total recognized tax benefit related to compensation cost for equity-based payment arrangements recognized in income during the period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (h)(1)(i)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

+ Details

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- Definition

The aggregate amount of noncash, equity-based employee remuneration. This may include the value of stock or unit options, amortization of restricted stock or units, and adjustment for officers' compensation. As noncash, this element is an add back when calculating net cash generated by operating activities using the indirect method.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3602-108585

+ Details

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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Components of Stock Based Compensation (Detail) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-based compensation			$ 20.2	$ 21.8
Tax benefits on stock-based compensation expense	$ 1.3	$ 4.7	14.2	13.4
To be settled with stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-related compensation expense	6.1	6.0	11.3	13.9
Employee contributions for above stock plans	3.8	3.4	8.9	7.9
Total stock-based compensation	9.9	9.4	20.2	21.8
Tax benefits on stock-based compensation expense	3.5	2.2	4.1	5.1
To be settled with stock \| Amortization of the grant date fair value
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-related compensation expense	0.0	0.1	0.0	1.0
To be settled with stock \| Cash payments in lieu of options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-related compensation expense	0.0	0.0	0.0	0.0
To be settled with stock \| Stock-based retirement plans contributions
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-related compensation expense	2.2	1.7	3.6	3.5
To be settled with stock \| Deferred Stock Compensation Program
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-related compensation expense	0.5	0.5	1.2	1.1
To be settled with stock \| Stock-based retirement plans
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-related compensation expense	0.4	0.3	0.7	0.7
To be settled with stock \| Discount Stock Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-related compensation expense	0.3	0.2	0.6	0.5
To be settled with stock \| Performance Stock Unit awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-related compensation expense	1.4	1.3	2.7	2.5
To be settled with stock \| Restricted Stock Unit awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-related compensation expense	0.6	0.7	1.2	1.4
To be settled with stock \| Profitable Growth Incentive awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-related compensation expense	0.4	0.9	0.8	2.5
To be settled with stock \| Other, primarily non-employee directors restricted stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-related compensation expense	0.3	0.3	0.5	0.7
To be settled in cash
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-related compensation expense	2.6	3.2	3.7	8.1
To be settled in cash \| Amortization of the grant date fair value
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-related compensation expense	0.0	0.0	0.0	0.0
To be settled in cash \| Cash payments in lieu of options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-related compensation expense	0.0	(0.1)	0.0	1.0
To be settled in cash \| Stock-based retirement plans contributions
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-related compensation expense	0.3	0.3	0.7	0.7
To be settled in cash \| Deferred Stock Compensation Program
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-related compensation expense	0.0	0.0	0.0	0.0
To be settled in cash \| Stock-based retirement plans
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-related compensation expense	0.0	0.0	0.0	0.0
To be settled in cash \| Discount Stock Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-related compensation expense	0.0	0.0	0.0	0.0
To be settled in cash \| Performance Stock Unit awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-related compensation expense	1.9	2.2	2.1	4.4
To be settled in cash \| Restricted Stock Unit awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-related compensation expense	0.0	0.0	0.0	0.0
To be settled in cash \| Profitable Growth Incentive awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-related compensation expense	0.4	0.8	0.9	2.0
To be settled in cash \| Other, primarily non-employee directors restricted stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-related compensation expense	0.0	0.0	0.0	0.0
Accounting Standards Update 2016-09 \| To be settled with stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Tax benefits on stock-based compensation expense	$ 2.2	$ 2.5	$ 10.1	$ 8.3