Stock-Based Awards Granted (Detail) - $ / shares shares in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2017	Jun. 30, 2017
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Shares, granted	169	3,082
Weighted-Average Grant Date Fair Value, granted	$ 12.06	$ 12.48
Service-Based Restricted Stock Units [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Shares, granted	128	1,897
Weighted-Average Grant Date Fair Value, granted	$ 11.93	$ 12.38
Performance-Based Restricted Stock Units with a Service Condition [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Shares, granted	0	572
Weighted-Average Grant Date Fair Value, granted	$ 0.00	$ 11.93
Market-Based Restricted Stock Units with a Service Condition [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Shares, granted	41	613
Weighted-Average Grant Date Fair Value, granted	$ 12.49	$ 13.34

The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(2)(iii)(1)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

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- Definition

The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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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.

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