Pension And Profit Sharing Plans (Narrative) (Detail) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Defined Benefit Plan Disclosure [Line Items]
Maximum annual compensation subject to pension	$ 1.5
Defined contribution pension [Member]
Defined Benefit Plan Disclosure [Line Items]
Contribution percentage of eligible employees compensation	10.00%
Vested after two years	20.00%
Vested after three years	60.00%
Vested after four years	80.00%
Vested after five years	100.00%
Pension expense	$ 3.0	$ 4.0	$ 4.0
Qualified profit-sharing/401(k) [Member]
Defined Benefit Plan Disclosure [Line Items]
Contribution percentage of eligible employees compensation	25.00%
Vested after two years	20.00%
Vested after three years	60.00%
Vested after four years	80.00%
Vested after five years	100.00%
Pension expense	$ 2.0	2.0	3.0
Contributions percentage of employer match	5.00%
Non-qualified pension [Member]
Defined Benefit Plan Disclosure [Line Items]
Pension expense	$ 1.0	2.0	2.0
Non-qualified profit-sharing/401(k) [Member]
Defined Benefit Plan Disclosure [Line Items]
Pension expense	$ 1.0	$ 1.0	$ 1.0

Maximum annual compensation per employee subject to pension contribution.

No definition available.

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- Definition

Percentage of pension benefits vested due after five years.

+ References

No definition available.

+ Details

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- Definition

Percentage of pension benefits vested due after four years.

+ References

No definition available.

+ Details

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- Definition

Percentage of pension benefits vested due after three years.

+ References

No definition available.

+ Details

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- Definition

Percentage of pension benefits vested due after two years.

+ References

No definition available.

+ 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 employer matches of the employee's percentage contribution matched.

+ References

No definition available.

+ Details

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- Definition

Maximum percentage of employee gross pay the employee may contribute to a defined contribution plan.

+ References

No definition available.

+ Details

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- Definition

The amount of pension benefit costs recognized during the period for (1) defined benefit plans and (2) defined contribution plans. For defined benefit plans, pension expense includes the following components: service cost, interest cost, expected return on plan assets, gain (loss) on plan assets, prior service cost or credit, transition asset or obligation, and gain (loss) due to settlements or curtailments. For defined contribution plans, the pension expense generally equals the firm's contribution to employees' accounts (if the firm contributes) during the period.

+ 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

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3602-108585

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=35743120&loc=d3e1928-114920

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (h)
-URI http://asc.fasb.org/extlink&oid=35743120&loc=d3e1928-114920

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- Details

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