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Share Based Compensation Arrangement by Share Based Payment Award, Performance Period

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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.

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The amount of expense, net of income tax, 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.

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The compensation expense recognized during the period pertaining to the deferred compensation arrangement.

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Unrecognized cost of unvested share-based compensation awards.

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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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Unrecognized cost of unvested share-based awards, other than options, awarded to employees as compensation.

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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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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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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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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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Amount of accumulated difference between fair value of underlying shares on dates of exercise and exercise price on options exercised (or share units converted) into shares.

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- Definition

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

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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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- Definition

Number of share instruments newly issued under a share-based compensation plan.

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- Definition

The floor of a customized range of exercise prices for purposes of disclosing shares potentially issuable under outstanding stock option awards on all stock option plans and other required information pertaining to awards in the customized range.

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The ceiling of a customized range of exercise prices for purposes of disclosing shares potentially issuable under outstanding stock option awards on all stock option plans and other required information pertaining to awards in the customized range.

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- Definition

Number of shares for which recognition of compensation cost was accelerated.

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No definition available.

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- Definition

Percentage of vesting of share-based compensation awards.

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Period from grant date that an equity-based award expires, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Stock-Based Compensation - Narrative (Detail) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended		6 Months Ended		12 Months Ended
	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Stock-Based Compensation
Stock-based compensation expense					$ 2.3	$ 2.4	$ 3.5
Number of share options granted during the period (in shares)			300,000	100,000
Exercise Price, low end of range					$ 4.41
Exercise Price, high end of range					$ 43.33
Share-based Compensation Arrangement by Share-based Payment Award, Accelerated Vesting, Number					100,000
Stock-based compensation expense	$ 1.8	$ 0.6	$ 2.6	$ 1.6
Separation expense	$ 1.3	$ 0.5	4.3	$ 0.5	$ 4.3	$ 0.0	0.0
Minimum
Stock-Based Compensation
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant						0
Maximum
Stock-Based Compensation
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant						100,000
Restricted Stock
Stock-Based Compensation
Stock-based compensation expense					0.5
Separation expense			$ 0.8
Shares issued			300,000	200,000
Stock Options
Stock-Based Compensation
Stock-based compensation expense					$ 0.6	$ 0.9	$ 1.7
Number of share options granted during the period (in shares)					400,000	100,000	100,000
Stock-based compensation expense, Net of Tax					$ 0.4	$ 0.5	$ 1.0
Unrecognized compensation expense					$ 1.4
Recognition period for unrecognized compensation expense					3 years 3 months 18 days
weighted average fair value of options granted per share					$ 9.71	$ 14.83	$ 9.00
Stock Options \| Director [Member]
Stock-Based Compensation
Expiration period					10 years
Stock Options \| Officers And Employees [Member] \| Prior To 2011 Grant [Member]
Stock-Based Compensation
Expiration period					10 years
Vesting rights percentage (as a percent)					25.00%
Vesting period (in years)					4 years
Stock Options \| Officers And Employees [Member] \| Two Thousand Eleven Equity Grants [Member]
Stock-Based Compensation
Expiration period					10 years
Vesting rights percentage (as a percent)					25.00%
Vesting period (in years)					4 years
Restricted Stock Units (RSUs) [Member]
Stock-Based Compensation
Stock-based compensation expense					$ 1.7	$ 0.9	$ 1.0
Stock-based compensation expense, Net of Tax					$ 1.1	$ 0.6	$ 0.6
Granted restricted performance stock units					200,000	100,000	100,000
Performance Shares
Stock-Based Compensation
Recognition period for unrecognized compensation expense					1 year 9 months 18 days
Granted restricted performance stock units					200,000
Unrecognized compensation expense					$ 1.7
2016 Plan
Stock-Based Compensation
Total intrinsic value of stock options exercised					$ 1.8	$ 8.0	$ 1.5
Number of shares of common stock authorized under the plan (in shares)	16,200,000		16,200,000
2016 Plan \| Stock Options
Stock-Based Compensation
Vesting rights percentage (as a percent)			25.00%
Vesting period (in years)			4 years
2016 Plan \| Performance Shares
Stock-Based Compensation
Vesting rights percentage (as a percent)			75.00%
Performance period			3 years