Number of common share received by the employee on vesting of restricted stock unit.

No definition available.

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- Definition

Share based compensation arrangement by share based payment award equity instruments other than options cancelled in Period.

+ References

No definition available.

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- Definition

Share based compensation arrangement by share based payments award equity instruments other than options cancelled in period weighted average grant date fair value.

+ References

No definition available.

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- Definition

Vested Stock [Abstract]

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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

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-Name Staff Accounting Bulletin (SAB)

-Number Topic 14

-Section F

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Unrecognized cost of unvested share-based compensation awards.

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-Publisher FASB

-Name Accounting Standards Codification

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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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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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-Section 50

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The number of equity-based payment instruments, excluding stock (or unit) options, that were forfeited during the reporting period.

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-Name Accounting Standards Codification

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-Paragraph 2

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- Definition

Weighted average fair value as of the grant date of equity-based award plans other than stock (unit) option plans that were not exercised or put into effect as a result of the occurrence of a terminating event.

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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).

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The weighted average fair value at grant date for nonvested equity-based awards issued 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).

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- Definition

The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

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-Paragraph 2

-Subparagraph (c)(2)(i)-(ii)

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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ References

No definition available.

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- Definition

The weighted average fair value of nonvested awards on equity-based plans excluding option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, revenue or profit achievement stock award plan) for which the employer is contingently obligated to issue equity instruments or transfer assets to an employee who has not yet satisfied service or performance criteria necessary to gain title to proceeds from the sale of the award or underlying shares or units.

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-Paragraph 2

-Subparagraph (c)(2)(i)-(ii)

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- Definition

The number of equity-based payment instruments, excluding stock (or unit) options, that vested during the reporting period.

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-Paragraph 2

-Subparagraph (c)(2)(iii)(2)

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The weighted average fair value as of grant date pertaining to an equity-based award plan other than a stock (or unit) option plan for which the grantee gained the right during the reporting period, by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash in accordance with the terms of the arrangement.

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-Name Accounting Standards Codification

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-SubTopic 10

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-Paragraph 2

-Subparagraph (c)(2)(iii)(2)

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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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No definition available.

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The maximum number of shares (or other type of equity) originally approved (usually by shareholders and board of directors), net of any subsequent amendments and adjustments, for awards under the equity-based compensation plan. As stock or unit options and equity instruments other than options are awarded to participants, the shares or units remain authorized and become reserved for issuance under outstanding awards (not necessarily vested).

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-SubTopic 10

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-Paragraph 2

-Subparagraph (a)(3)

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The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

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-SubTopic 10

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- Definition

The number of shares under options that were cancelled during the reporting period as a result of occurrence of a terminating event specified in contractual agreements pertaining to the stock option plan.

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-Publisher FASB

-Name Accounting Standards Codification

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-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)(1)(iv)(3)

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- Definition

Gross number of share options (or share units) granted during the period.

+ References

No definition available.

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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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-Publisher FASB

-Name Accounting Standards Codification

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-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (d)(1)

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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ References

No definition available.

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Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan.

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-Name Accounting Standards Codification

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-Paragraph 2

-Subparagraph (c)(1)(i)

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As of the balance sheet date, the number of shares into which fully vested and expected to vest stock options outstanding can be converted under the option plan.

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-Name Accounting Standards Codification

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-Paragraph 2

-Subparagraph (e)(1)

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Percentage of vesting of share-based compensation awards.

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Weighted average remaining contractual term for vested portions of options outstanding and currently exercisable or convertible, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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For net-share settlement of share-based awards when the employer settles employees' income tax withholding obligations, this element represents the number of shares the employees use to repay the employer.

+ References

No definition available.

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Number of share options (or share units) exercised during the current period.

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-Name Accounting Standards Codification

-Topic 505

-SubTopic 10

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-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 29, 30

-Article 5

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Value of stock issued in lieu of cash for services contributed to the entity. Value of the stock issued includes, but is not limited to, services contributed by vendors and founders.

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No definition available.

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Employee Incentive Plans, Long term Incentive Plans (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended		6 Months Ended		12 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014	Dec. 31, 2014
Share-based Compensation Arrangement by Share-based Payment Award
Number of common shares authorized for issuance under Equity Incentive Plan	2,722,222		2,722,222
Number of common shares available for additional awards under Equity Incentive Plan	706,471		706,471
Non-cash compensation expense	$ 2.4	$ 2.3	$ 4.6	$ 4.3
Stock Options
Fully-vested options outstanding	16,645		16,645		16,645
Exercise price of options to purchase common stock	$ 80.01		$ 80.01		$ 80.01
Remaining contractual life of options outstanding			1 year 9 months		2 years 3 months
Grant date fair value of options outstanding			$ 39.90		$ 39.90
Stock options granted			0
Stock options forfeited	0
Stock options exercised	0
Vested Stock
Issuance of common shares to non-employee directors			$ 0.2
Common shares withheld and canceled			34,969	33,006
Fabricated Products
Share-based Compensation Arrangement by Share-based Payment Award
Non-cash compensation expense	$ 0.9	1.1	$ 1.6	$ 2.1
All Other
Share-based Compensation Arrangement by Share-based Payment Award
Non-cash compensation expense	$ 1.5	1.2	$ 3.0	2.2
Non-vested common shares
Summary of Activity
Outstanding at December 31, 2014			158,770
Weighted-Average Grant-Date Fair Value per Share			$ 59.88
Granted, shares			62,285
Granted, Weighted-Average Grant-Date Fair Value per Share			$ 71.67
Vested, shares			(57,849)
Vested, Weighted-Average Grant-Date Fair Value per Share			$ 52.68
Forfeited, shares			(540)
Forfeited, Weighted-Average Grant-Date Fair Value per Share			$ 66.89
Canceled, Shares			0
Canceled, Weighted-Average Grant-Date Fair Value per Share			$ 0
Outstanding at June 30, 2015	162,666		162,666		158,770
Weighted-Average Grant-Date Fair Value per Share	$ 66.93		$ 66.93		$ 59.88
Restricted stock units (RSUs)
Share-based Compensation Arrangement by Share-based Payment Award
Number of common shares received by the employee on vesting of restricted stock unit			1
Summary of Activity
Outstanding at December 31, 2014			5,357
Weighted-Average Grant-Date Fair Value per Share			$ 59.71
Granted, shares			2,325
Granted, Weighted-Average Grant-Date Fair Value per Share			$ 69.83
Vested, shares			(2,161)
Vested, Weighted-Average Grant-Date Fair Value per Share			$ 52.91
Forfeited, shares			0
Forfeited, Weighted-Average Grant-Date Fair Value per Share			$ 0
Canceled, Shares			0
Canceled, Weighted-Average Grant-Date Fair Value per Share			$ 0
Outstanding at June 30, 2015	5,521		5,521		5,357
Weighted-Average Grant-Date Fair Value per Share	$ 66.64		$ 66.64		$ 59.71
Non-vested common shares and restricted stock units
Share-based Compensation Arrangement by Share-based Payment Award
Non-cash compensation expense	$ 1.1	1.2	$ 2.2	2.3
Unrecognized gross compensation costs (in millions of dollars)	8.0		$ 8.0
Expected period (in years) over which the remaining gross compensation costs will be recognized			2 years 2 months
EVA-Based Performance Shares
Share-based Compensation Arrangement by Share-based Payment Award
Performance award vesting period, years			3 years
Non-cash compensation expense	0.3	0.5	$ 0.7	1.0
Unrecognized gross compensation costs (in millions of dollars)	$ 0.9		$ 0.9
Expected period (in years) over which the remaining gross compensation costs will be recognized			8 months
Summary of Activity
Outstanding at December 31, 2014			353,576
Weighted-Average Grant-Date Fair Value per Share			$ 50.35
Granted, shares			0
Granted, Weighted-Average Grant-Date Fair Value per Share			$ 0.00
Vested, shares			(48,648)
Vested, Weighted-Average Grant-Date Fair Value per Share			$ 44.48
Forfeited, shares			(432)
Forfeited, Weighted-Average Grant-Date Fair Value per Share			$ 57.54
Canceled, Shares			(146,016)
Canceled, Weighted-Average Grant-Date Fair Value per Share			$ 44.48
Outstanding at June 30, 2015	158,480		158,480		353,576
Weighted-Average Grant-Date Fair Value per Share	$ 57.75		$ 57.75		$ 50.35
TSR-Based Performance Shares
Share-based Compensation Arrangement by Share-based Payment Award
Non-cash compensation expense	$ 1.0	$ 0.6	$ 1.7	$ 1.0
Unrecognized gross compensation costs (in millions of dollars)	$ 9.9		$ 9.9
Expected period (in years) over which the remaining gross compensation costs will be recognized			2 years 5 months
Summary of Activity
Outstanding at December 31, 2014			150,223
Weighted-Average Grant-Date Fair Value per Share			$ 83.18
Granted, shares			150,424
Granted, Weighted-Average Grant-Date Fair Value per Share			$ 95.68
Vested, shares			0
Vested, Weighted-Average Grant-Date Fair Value per Share			$ 0
Forfeited, shares			(404)
Forfeited, Weighted-Average Grant-Date Fair Value per Share			$ 83.18
Canceled, Shares			0
Canceled, Weighted-Average Grant-Date Fair Value per Share			$ 0
Outstanding at June 30, 2015	300,243		300,243		150,223
Weighted-Average Grant-Date Fair Value per Share	$ 89.44		$ 89.44		$ 83.18
Minimum \| EVA-Based Performance Shares
Share-based Compensation Arrangement by Share-based Payment Award
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights, Percentage	0.00%
Minimum \| TSR-Based Performance Shares
Share-based Compensation Arrangement by Share-based Payment Award
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights, Percentage	0.00%
Maximum \| EVA-Based Performance Shares
Share-based Compensation Arrangement by Share-based Payment Award
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights, Percentage	200.00%
Maximum \| TSR-Based Performance Shares
Share-based Compensation Arrangement by Share-based Payment Award
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights, Percentage	200.00%