Defined benefit plan assumptions used calculating plan assets expected long term return on assets.

No definition available.

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- Definition

Defined contribution plan contribution rates as a percentage of employees earnings.

+ References

No definition available.

+ Details

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- Definition

Defined contribution plan matching percent of compensation.

+ References

No definition available.

+ Details

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- 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=6414718&loc=d3e28014-114942

+ 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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- Details

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- Details

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Pension Plans and Postretirement Benefits - Additional Information (Detail) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Domestic Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Expected rate of return on plan assets	5.00%
Employer contributions, percentage match of participants' contributions	50.00%
Employer contributions, percentage unmatched of participants' contributions	3.00%
Defined contribution plans costs	$ 3.9	$ 6.4	$ 6.8
Domestic Plans [Member] \| Maximum [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined contribution plan matching percent of compensation	6.00%
TCN Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Expected rate of return on plan assets	6.90%
Employer contributions, percentage match of participants' contributions	50.00%
Employer contributions, percentage unmatched of participants' contributions	3.00%
Defined contribution plans costs	$ 1.2	$ 1.6	$ 1.6
TCN Plan [Member] \| Maximum [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined contribution plan matching percent of compensation	6.00%