Defined benefit plans revisions effective date, in YYYY-MM-DD format.

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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

Amount of discretionary contributions made by an employer to a defined contribution plan.

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- Definition

Percentage of employees' gross pay for which the employer contributes a matching contribution to a defined contribution plan.

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Percentage employer matches of the employee's percentage contribution matched.

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Employee Benefits 401(k) Defined Contribution Plans (Details) - USD ($) $ in Millions			12 Months Ended
	Apr. 02, 2014	Mar. 31, 2014	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Defined Contribution Plan Disclosure [Line Items]
Defined benefit plans revisions effective date	Apr. 01, 2014
Defined Contribution Plan, Employer Discretionary Contribution Amount			$ 4.1	$ 3.9	$ 3.0
Defined Contribution Plan, Employer Matching Contribution, Percent of Match	100.00%	50.00%
Maximum
Defined Contribution Plan Disclosure [Line Items]
Defined Contribution Plan, Employer Matching Contribution, Percent	6.00%	6.00%