Employee Benefit Plans (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Defined Benefit Plan, Net Periodic Benefit Cost [Abstract]
Net periodic pension cost, U.S. Plans	$ 7,660hsc_NetPeriodPensionCostsDomestic	$ 21,379hsc_NetPeriodPensionCostsDomestic	$ 20,673hsc_NetPeriodPensionCostsDomestic
Net periodic pension cost, International Plans	19,054hsc_NetPeriodPensionCostsForeign	32,242hsc_NetPeriodPensionCostsForeign	35,861hsc_NetPeriodPensionCostsForeign
U.S. Plans
Defined Benefit Plan, Net Periodic Benefit Cost [Abstract]
Multiemployer plans	1,199	12,444	10,186
International Plans
Defined Benefit Plan, Net Periodic Benefit Cost [Abstract]
Multiemployer plans	1,762	5,449	5,539
U.S. Plans
Defined Benefit Plan, Net Periodic Benefit Cost [Abstract]
Defined contribution plans	4,704	4,945	5,066
U.S. Plans \| Maximum
Defined Contribution Pension and Other Postretirement Plans Disclosure [Abstract]
Employer matching contribution (as a percent)	4.00%
Employer discretionary contribution (as a percent)	2.00%
International Plans
Defined Contribution Pension and Other Postretirement Plans Disclosure [Abstract]
Additional contribution towards insurance and administrative costs (as a percent)	2.00%
Defined Benefit Plan, Net Periodic Benefit Cost [Abstract]
Defined contribution plans	8,033	11,139	12,770
International Plans \| Maximum
Defined Contribution Pension and Other Postretirement Plans Disclosure [Abstract]
Employer matching contribution (as a percent)	6.00%
U.S. Plans
Defined Benefit Plan, Net Periodic Benefit Cost [Abstract]
Service cost	2,233	2,565	1,887
Interest cost	12,868	11,767	12,780
Expected return on plan assets	(16,786)	(15,642)	(15,617)
Recognized prior service costs	90	248	224
Recognized losses	3,352	5,052	4,637
Amortization of transition liability	0	0	0
Settlement/curtailment loss (gain)	0	0	1,510
Defined benefit plans pension cost	1,757	3,990	5,421
International Plans
Defined Benefit Plan, Net Periodic Benefit Cost [Abstract]
Service cost	1,610	3,457	3,418
Interest cost	43,230	42,707	46,174
Expected return on plan assets	(49,927)	(46,920)	(45,050)
Recognized prior service costs	184	335	397
Recognized losses	14,102	16,447	15,194
Amortization of transition liability	0	0	8
Settlement/curtailment loss (gain)	60	(372)	(2,589)
Defined benefit plans pension cost	$ 9,259	$ 15,654	$ 17,552

Defined Contribution Plan, Employer Discretionary Contribution, Percentage

No definition available.

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- Definition

Represents the percentage of participants' compensation for which the entity makes a contribution to the defined contribution plan for non-U.S. employees to cover insurance and administrative costs.

+ References

No definition available.

+ Details

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- Definition

Amount of expense related to multiemployer plans for each period for which a statement of income is presented.

+ References

No definition available.

+ Details

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- Definition

The total amount of domestic net periodic pension cost for defined benefit plans, defined contribution plans and multiemployer plans for the period.

+ References

No definition available.

+ Details

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- Definition

Net Period Pension Costs, Foreign

+ References

No definition available.

+ Details

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- Definition

The amount of gains or losses recognized in net periodic benefit cost.

+ References

+ Details

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- Definition

The amount of the prior service cost or credit recognized in net periodic benefit cost relating to benefit changes attributable to plan participants' prior service pursuant to a plan amendment or a plan initiation.

+ References

+ Details

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- Definition

The amount of the transition obligation or asset recognized in net periodic benefit cost.

+ References

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- Definition

An amount calculated as a basis for determining the extent of delayed recognition of the effects of changes in the fair value of assets. The expected return on plan assets is determined based on the expected long-term rate of return on plan assets and the market-related value of plan assets.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 30

-Glossary Expected Return on Plan Assets

-URI http://asc.fasb.org/extlink&oid=6512136

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 60

-Glossary Expected Return on Plan Assets

-URI http://asc.fasb.org/extlink&oid=6512171

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (h)(3)

-URI http://asc.fasb.org/extlink&oid=35743120&loc=d3e1928-114920

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- Definition

The increase in a defined benefit pension plan's projected benefit obligation or a defined benefit postretirement plan's accumulated postretirement benefit obligation due to the passage of time.

+ References

+ Details

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- Definition

The total amount of net periodic benefit cost for defined benefit plans for the period. Periodic benefit costs include the following components: service cost, interest cost, expected return on plan assets, gain (loss), prior service cost or credit, transition asset or obligation, and gain (loss) due to settlements or curtailments.

+ References

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- Definition

Amount of net gain (loss) recognized in net periodic benefit cost due to settlements and curtailments. Curtailments result from an event that significantly reduces the expected years of future service of present employees or eliminates for a significant number of employees the accrual of defined benefits for some or all of their future services. Settlements result from an irrevocable action that relieves the employer (or the plan) of primary responsibility for a benefit obligation and eliminates significant risks related to the obligation and the assets used to effect the settlement. Examples of transactions that constitute a settlement include, but are not limited to, lump-sum cash payments to plan participants in exchange for their rights to receive specified benefits and purchasing nonparticipating annuity contracts to cover vested benefits.

+ References

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- Definition

The actuarial present value of benefits attributed by the pension benefit formula to services rendered by employees during the period. The portion of the expected postretirement benefit obligation attributed to employee service during the period. The service cost component is a portion of the benefit obligation and is unaffected by the funded status of the plan.

+ 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 (h)(1)

-URI http://asc.fasb.org/extlink&oid=35743120&loc=d3e1928-114920

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Service Cost (Component of Net Periodic Pension Cost)

-URI http://asc.fasb.org/extlink&oid=6525008

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (a)(1)

-URI http://asc.fasb.org/extlink&oid=35743120&loc=d3e1928-114920

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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=6414718&loc=d3e28014-114942

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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.

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