Employee Stock Purchase Plan, Employer Matching Contribution, Percent of Match

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Employee Stock Purchase Plan, Maximum Annual Contributions Per Employee, Percent

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- Definition

Reclassification of performance share unit liability to equity as a result of modification of the award to provide the Company with the option to settle through share issuance, and then reclassification from permanent equity to temporary equity as the performance share units are contingently redeemable in cash in the event of death of the participant.

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- Definition

Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grant Date Fair Value

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- Definition

Fair value of share-based awards for which the grantee gained the right by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash. Additionally, share-based awards which were paid or settled.

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No definition available.

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- Definition

Share Based Compensation Arrangement By Share Based Payment Award, Number Of Plans

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No definition available.

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- Definition

Share Based Compensation Arrangement By Share Based Payment Award, Number Of Units Available For Grant As Percentage Of Target

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- Definition

Share-based Compensation Arrangement by Share-based Payment Award, Options, Assumed in Period, Weighted Average Grant Date Fair Value

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No definition available.

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- Definition

Share-based Compensation Arrangement by Share-based Payment Award, Term of Award

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- Definition

Shares to be issued for settlement.

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No definition available.

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- Definition

Aggregate number of common shares reserved for future issuance.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.29)
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- Definition

Unrecognized cost of unvested share-based compensation awards.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (i)
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- Definition

Weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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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.

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-Publisher FASB
-Name Accounting Standards Codification
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- Definition

Amount of cash inflow from exercise of stock options granted under share-based compensation arrangement.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
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- Definition

Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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- Definition

The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
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-Paragraph 2
-Subparagraph (c)(2)(iii)(1)
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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.

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- Definition

The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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- Definition

The weighted average of per share prices paid for shares purchased on the open market for issuance to employees under the plan.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
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- Definition

Intrinsic value of equity-based compensation awards outstanding. Excludes stock and unit options.

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No definition available.

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Share-Based Payments (Narrative) (Details)				12 Months Ended
Share-Based Payments (Narrative) (Details)	Nov. 08, 2017 USD ($)	May 01, 2017 USD ($) $ / shares shares	Aug. 11, 2014 shares	Dec. 31, 2017 USD ($) item $ / shares shares	Dec. 31, 2016 USD ($) $ / shares shares	Dec. 31, 2015 USD ($) $ / shares shares	May 02, 2016 shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share units reclassified to temporary equity				$ (382,000)	$ (70,000)
Maximum employee contribution, percentage				4.00%
Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Employer matching contribution, percentage				50.00%
Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Employer matching contribution, percentage				100.00%
Stock Option Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period				5 years
Award term				10 years
Remaining shares authorized for grant \| shares				3,402,481	4,202,631
Weighted average share price of options exercised \| $ / shares				$ 30.81	$ 31.18	$ 27.78
Weighted average grant date fair value of options granted \| $ / shares				$ 7.22	$ 4.72	$ 5.39
Unrecognized compensation costs				$ 6,610,000
Unrecognized compensation costs, period for recognition				2 years 2 months 12 days
Proceeds from exercise of employee stock options				$ 9,935,000	$ 24,338,000	$ 29,816,000
Actual tax benefit realized from option exercise				1,017,000	1,464,000	1,150,000
Performance Share Unit Plans [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Market value of shares vested and released				6,521,000	4,463,000	$ 1,253,000
Share unit liability				$ 8,274,000	$ 14,665,000
Senior Executive and Employee Performance Share Unit Plans [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Remaining shares authorized for grant \| shares							1,000,000
Weighted average grant date fair value of options granted \| $ / shares				$ 27.34
Share unit liability				$ 2,105,000
Share units reclassified to temporary equity				$ 2,175,000
Senior Executive and Employee Performance Share Unit Plans [Member] \| Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of units available for grant as a percentage of target				0.00%
Senior Executive and Employee Performance Share Unit Plans [Member] \| Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of units available for grant as a percentage of target				200.00%
Stock Options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of plans \| item				3
Stock Options Assumed [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted average share price of options assumed \| $ / shares				$ 16.93
Performance Share Units, Equity Classified Awards [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation costs				$ 5,280,000
Unrecognized compensation costs, period for recognition				1 year 8 months 12 days
Granted, Shares \| shares				136,073	7,714
Performance Share Units, Liability Classified Awards [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation costs				$ 3,163,000
Unrecognized compensation costs, period for recognition				1 year 7 months 6 days
Granted, Shares \| shares				98,775	257,117	218,699
Performance Share Units [Member] \| Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of units available for grant as a percentage of target				0.00%
Performance Share Units [Member] \| Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of units available for grant as a percentage of target				200.00%
Performance Share Units [Member] \| Sign-on Grant Performance Share Unit Plans [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Remaining shares authorized for grant \| shares		150,000
Weighted average grant date fair value of options granted \| $ / shares		$ 24.47
Granted, Shares \| shares			102,375
Share unit liability, fair value attributable to past service		$ 1,421,000
Share units reclassified to temporary equity		$ 1,803,000
Performance Share Units [Member] \| Sign-on Grant Performance Share Unit Plans [Member] \| Tranche One [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period				2 years
Performance Share Units [Member] \| Sign-on Grant Performance Share Unit Plans [Member] \| Tranche Two [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period				3 years
Performance Share Units [Member] \| Sign-on Grant Performance Share Unit Plans [Member] \| Tranche Three [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period				4 years
Performance Share Units [Member] \| Sign-on Grant Performance Share Unit Plans [Member] \| Tranche Four [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period				5 years
Restricted Share Units [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares to be issued for settlement.	$ 300,000
Restricted Stock Units, Liability Classified Awards [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation costs				$ 37,000
Unrecognized compensation costs, period for recognition				9 months 18 days
Granted, Shares \| shares				878	4,543	20,528
Restricted Stock Units, Equity Classified [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation costs				$ 2,980,000
Unrecognized compensation costs, period for recognition				2 years 10 months 24 days
Granted, Shares \| shares				125,152
Deferred Share Units [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted, Shares \| shares				19,967	17,371	29,072