Defined Contribution Plan, Annual Contribution By Employee, Maximum Allowable Amount, Percent

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- Definition

Defined Contribution Plan, Annual Contribution By Employee, Minimum Allowable Amount, Percent

+ References

No definition available.

+ Details

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- Definition

Defined Contribution Plan, Employers Matching Contribution, Vesting Period

+ References

No definition available.

+ Details

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- Definition

Defined Contribution Plan, Requisite Service Period

+ References

No definition available.

+ Details

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- References

No definition available.

+ Details

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- Definition

The amount of the cost recognized during the period for defined contribution plans.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 70
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=49170846&loc=d3e28014-114942

+ Details

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- Definition

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

+ References

No definition available.

+ Details

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- Definition

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

+ References

No definition available.

+ Details

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- Definition

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

+ References

No definition available.

+ Details

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Employee Benefits - Narrative (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
401 (k) Retirement Plan [Abstract]
Minimum service period for plan eligibility	6 months
Minimum allowable contribution to the plan by each employee, percent	1.00%
Maximum allowable contribution to the plan by each employee, percent	80.00%
Employers matching contribution, vesting period	4 years
Company contributions to the plan	$ 1.4	$ 1.4	$ 1.2
Range 1
401 (k) Retirement Plan [Abstract]
Employer matching contribution, percent	100.00%
Employer matching contribution, percent of employees' gross pay	2.00%
Range 2
401 (k) Retirement Plan [Abstract]
Employer matching contribution, percent	50.00%
Employer matching contribution, percent of employees' gross pay	2.00%
AGC Southwest Chapters 401(k) Retirement Plan
401 (k) Retirement Plan [Abstract]
Employer matching contribution, percent	50.00%
Employer matching contribution, percent of employees' gross pay	6.00%
Employer discretionary contribution amount	$ 0.2	$ 0.1