Employer investment in qualified defined contribution plan.

No definition available.

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- Definition

Age in which estimates of social security benefits received will be incorporated for purpose of determining pension benefits.

+ References

No definition available.

+ Details

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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.

+ References

No definition available.

+ Details

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- Definition

Amount of employer's best estimate of contributions expected to be paid to the plan during the next fiscal year beginning after the date of the latest statement of financial position.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (g)
-URI http://asc.fasb.org/extlink&oid=65897934&loc=d3e1928-114920

+ Details

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Balance Type:	debit
Period Type:	duration

- Definition

Maximum percentage of employee gross pay the employee may contribute to a defined contribution plan.

+ References

No definition available.

+ Details

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- Definition

The amount of cash or cash equivalents contributed by the entity to fund its pension plans.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 25
-Subparagraph (g)
-URI http://asc.fasb.org/extlink&oid=66902209&loc=d3e3536-108585

+ Details

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Balance Type:	credit
Period Type:	duration

- Details

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- Details

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Pension, Savings, And Other Employee Benefits (Narrative) (Details) - USD ($) $ in Thousands	3 Months Ended			12 Months Ended
	Mar. 31, 2017	Sep. 30, 2016	Mar. 31, 2016	Dec. 31, 2017	Dec. 31, 2016
Defined Benefit Plan Disclosure [Line Items]
Estimated social security benefits age	65 years
Contributions to qualified plans	$ 0	$ 165,000	$ 0
Non-Qualified Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Contributions to qualified plans					$ 5,100
Expected pension contribution				$ 5,000
Savings Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Employer investment in qualified defined contribution plan	100.00%		100.00%
Maximum percent of employee pre-tax contributions that may be matched by the Company	6.00%		6.00%