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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- Definition

For a classified balance sheet, the amount recognized in balance sheet as a current asset associated with 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 (c)
-URI http://asc.fasb.org/extlink&oid=58740216&loc=d3e1928-114920

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=21915240&loc=d3e1703-114919

+ 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

Percentage of fair value of investments (categorized by debt securities, equity securities, real estate and other plan assets) to the fair value of plan assets held.

+ 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)
-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)(1)
-URI http://asc.fasb.org/extlink&oid=58740216&loc=d3e1928-114920

+ 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=49170846&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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Pension and Postretirement Benefits - Additional Information (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2016
Domestic Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Weighted average asset allocations, by asset category	100.00%	100.00%
Employer contributions, percentage match of participants' contributions	50.00%
Employer contributions, percentage unmatched of participants' contributions	3.00%
Defined contribution plans costs	$ 4	$ 4	$ 6
Domestic Plans [Member] \| Fixed Income [Member]
Defined Benefit Plan Disclosure [Line Items]
Weighted average asset allocations, by asset category	85.00%	85.00%
Domestic Plans [Member] \| Equity Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Weighted average asset allocations, by asset category	15.00%	15.00%
Domestic Plans [Member] \| Minimum [Member]
Defined Benefit Plan Disclosure [Line Items]
Expected rate of return on plan assets	4.20%
Domestic Plans [Member] \| Maximum [Member]
Defined Benefit Plan Disclosure [Line Items]
Expected rate of return on plan assets	5.00%
Defined contribution plan matching percent of compensation	6.00%
TCN Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Weighted average asset allocations, by asset category	100.00%	100.00%
Employer contributions, percentage match of participants' contributions	50.00%
Employer contributions, percentage unmatched of participants' contributions	3.00%
Defined contribution plans costs	$ 1	$ 1	$ 2
TCN Plan [Member] \| Fixed Income [Member]
Defined Benefit Plan Disclosure [Line Items]
Weighted average asset allocations, by asset category	49.00%	28.00%
TCN Plan [Member] \| Fixed Income [Member] \| Scenario Forecast [Member]
Defined Benefit Plan Disclosure [Line Items]
Weighted average asset allocations, by asset category				70.00%
TCN Plan [Member] \| Equity Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Weighted average asset allocations, by asset category	51.00%	72.00%
TCN Plan [Member] \| Equity Securities [Member] \| Scenario Forecast [Member]
Defined Benefit Plan Disclosure [Line Items]
Weighted average asset allocations, by asset category				30.00%
TCN Plan [Member] \| Cash and Cash Equivalents [Member]
Defined Benefit Plan Disclosure [Line Items]
Plan assets held in cash in cash equivalents	$ 14
TCN Plan [Member] \| Minimum [Member]
Defined Benefit Plan Disclosure [Line Items]
Expected rate of return on plan assets	4.70%
TCN Plan [Member] \| Maximum [Member]
Defined Benefit Plan Disclosure [Line Items]
Expected rate of return on plan assets	6.90%
Defined contribution plan matching percent of compensation	6.00%