Share-Based Compensation and Benefit Plans (Profit Sharing and Savings Plan) (Narrative) (Detail) - Profit sharing and savings plan [Member] - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Share-Based Compensation and Benefit Plans
Profit sharing and savings plan, description	The Company sponsors a contributory profit sharing and savings plan (the "401(k) Plan") that covers substantially all employees who are at least 21 years of age and have at least six months of service. The Company makes matching contributions equal to 100% of the first 2% of each employee's wages that are contributed and 25% of the next 4% of each employee's wages that are contributed.
Profit sharing and savings plan, employer discretionary contribution	$ 0.0	$ 0.0	$ 0.0
Profit sharing and savings plan, cost recognized	$ 18.5	$ 16.8	$ 16.5
Employee's first 2% of contributed wages [Member]
Share-Based Compensation and Benefit Plans
Profit sharing and savings plan, Company match	100.00%
Employee's next 4% of contributed wages [Member]
Share-Based Compensation and Benefit Plans
Profit sharing and savings plan, Company match	25.00%

The amount of the cost recognized during the period for defined contribution plans.

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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

Amount of discretionary contributions made by an employer to a defined contribution plan.

+ 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

Description of the terms and benefits provided by the employer's defined contribution plans. A defined contribution plan provides benefits in return for services rendered, provides an individual account for each participant, and has terms that specify how contributions to the individual's account are to be determined rather than the amount of benefits the individual is to receive. Under a defined contribution pension plan, the benefits a participant will receive depend solely on the amount contributed to the participant's account, the returns earned on investments of those contributions, and forfeitures of other participants' benefits that may be allocated to such participant's account. A description of the plan(s) including employee groups covered, the basis for determining contributions, and the nature and effects of significant matters affecting comparability of information for all periods presented.

+ 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

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Defined Contribution Plan
-URI http://asc.fasb.org/extlink&oid=49180617

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