Number of persons employed by the Entity

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- Definition

Guarantor Obligation, Estimated Exposure, Undiscounted

+ References

No definition available.

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- Definition

Operating Lease and Short-term Lease, Cost

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No definition available.

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- Definition

For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- References

No definition available.

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- Definition

The total amount of the contingent obligation under letters of credit outstanding as of the reporting date.

+ References

No definition available.

+ Details

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- Definition

Rental expense for the reporting period incurred under operating leases, including minimum and any contingent rent expense, net of related sublease income.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/otherTransitionRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 840
-SubTopic 20
-Section 50
-Paragraph 1
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- References

No definition available.

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- Definition

Amount of the fixed and determinable portion of the unrecorded unconditional purchase obligation maturing in the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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-Name Accounting Standards Codification
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-SubTopic 10
-Section 50
-Paragraph 4
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- Definition

Amount of the fixed and determinable portion of the unrecorded unconditional purchase obligation maturing in the next fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

+ Details

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- Definition

Amount of the fixed and determinable portion of the unrecorded unconditional purchase obligation maturing in the fourth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

+ Details

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- Definition

Amount of the fixed and determinable portion of the unrecorded unconditional purchase obligation maturing in the second fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

+ Details

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- Definition

Amount of the fixed and determinable portion of the unrecorded unconditional purchase obligation maturing in the third fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

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- Definition

Amount of the unrecorded obligation to transfer funds in the future for fixed or minimum amounts or quantities of goods or services at fixed or minimum prices (for example, as in take-or-pay contracts or throughput contracts).

+ References

+ Details

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- Definition

Amount of the fixed and determinable portion of the unrecorded unconditional purchase obligation maturing after the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

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Commitments and Contingencies (Details) $ in Thousands	12 Months Ended
Commitments and Contingencies (Details) $ in Thousands	Dec. 31, 2019 USD ($) employee	Dec. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)
Leases, Operating [Abstract]
Rental expense for operating leases	$ 7,000
Rental expense for operating leases		$ 8,000	$ 6,000
Purchase Obligations
2020	74,663
2020	48,881
2021	41,604
2022	29,376
2023	11,022
Thereafter	101,679
Total	$ 307,225
Number of employees \| employee	4,000
Concentration risk percentage	100.00%	100.00%	100.00%
Standby letters of credit
Purchase Obligations
Amount of letters of credit outstanding	$ 37,000
Surety bonds
Purchase Obligations
Guarantee	86,000
LTF project
Purchase Obligations
Guarantee	$ 31,000
Unionized Employees Concentration Risk
Purchase Obligations
Concentration risk percentage	74.00%