Represents the amount of investment made by the entity in United States Treasury securities and money market funds.

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Amount of increase (decrease) in additional paid in capital (APIC) resulting from a tax benefit (deficiency) associated with an share-based compensation plan other than an employee stock ownership plan (ESOP).

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No definition available.

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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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No definition available.

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- Definition

Percentage of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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

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Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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- Definition

Amount, before valuation and last-in first out (LIFO) reserves, of costs capitalized in inventory classified as other, expected to be sold, or consumed within one year or operating cycle, if longer.

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The cash inflow associated with the amount received from holders exercising their stock options. This item inherently excludes any excess tax benefit, which the entity may have realized and reported separately.

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Estimated period over which an employee is required to provide service in exchange for the equity-based payment award, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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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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- Definition

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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Fair value of options vested. Excludes equity instruments other than options, for example, but not limited to, share units, stock appreciation rights, restricted stock.

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Basis of Presentation - Accounting for Stock-Based Compensation (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended		12 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016	Dec. 31, 2016
Stock-based compensation activity, including both continuing and discontinued operations
Stock-based compensation expense recognized in operating expenses	$ 2,986	$ 3,373	$ 10,572	$ 5,853
Less: Tax benefit of stock-based compensation expense in provision for income taxes	1,079	1,204	3,870	2,122
Stock-based compensation expense, net of tax	1,907	2,169	6,702	3,731
Fair value of shares vested	2,687	3,601	10,337	5,951
Proceeds to the Company from the exercise of stock-based compensation	983	1,512	1,297	2,525
Tax effect from the exercise of stock-based compensation, including shortfall tax benefits	0	5	0	19	$ 232
Fair value of financial instruments
United States Treasury securities and money market funds	$ 3,438	$ 35,043	$ 3,438	$ 35,043	$ 2,832
Income Taxes
Effective tax rate (as a percent)	37.20%	35.80%	32.20%	36.70%
Provision for income taxes	$ 16,712	$ 14,640	$ 24,392	$ 24,703
Stock Compensation Plan
Stock-based compensation activity, including both continuing and discontinued operations
Stock-based compensation cost capitalized in inventory	$ 200	$ 500	$ 200	$ 500
1994 Plan
Stock-Based Compensation
Requisite service period			4 years
Expiration period			7 years
2011 Plan
Stock-Based Compensation
Maximum common stock shares that may be issued under plan (in shares)	150,000		150,000
2011 Plan \| Stock Options
Stock-Based Compensation
Maximum common stock shares that may be issued under plan (in shares)	16,300,000		16,300,000
2011 Plan \| Restricted Stock Units
Stock-Based Compensation
Maximum common stock shares that may be issued under plan (in shares)	100,000		100,000