Pension Plans (Details Textual) $ in Millions	12 Months Ended
Dec. 31, 2015 USD ($) plan
Defined Benefit Plan Disclosure [Line Items]
Number of defined benefit plans \| plan	3
Number of defined benefit pension plans covering certain employees at designated repair facilities \| plan	2
Expected employer contributions to pension plans next fiscal year \| $	$ 0.1
Pension Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Net actuarial loss (gain) expected to be amortized from accumulated other comprehensive loss \| $	$ (0.8)
Equity [Member]
Defined Benefit Plan Disclosure [Line Items]
Average target investment mix percentage	65.00%
Fixed Income [Member]
Defined Benefit Plan Disclosure [Line Items]
Average target investment mix percentage	35.00%

Number of total defined benefit plans the company sponsors

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- Definition

Number of Defined Benefit Pension Plans

+ References

No definition available.

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Amount included in accumulated other comprehensive income (AOCI) expected to be recognized as components of net periodic benefit cost for the fiscal year that follows the most recent annual statement of financial position, including gain (loss), prior service cost (credit), and transition asset (obligation).

+ References

No definition available.

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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.

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- Definition

Target allocation of investments of this type to total plan assets presented on a weighted average basis.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 5
-Subparagraph (c)(i)
-URI http://asc.fasb.org/extlink&oid=58740216&loc=d3e2446-114920

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (d)(i)
-URI http://asc.fasb.org/extlink&oid=58740216&loc=d3e1928-114920

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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=58740216&loc=d3e1928-114920

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