v3.7.0.1

Stock-based Compensation - Summary of Terms of Restricted Shares (Detail) - $ / shares shares in Thousands | 12 Months Ended
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Dec. 31, 2016 | Dec. 31, 2015
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |
Number of Shares | 2,517 |
Restricted Stock [Member] |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |
Number of Shares | 900 | 770
Weighted Average Grant- date Fair Value | $ 15.45 | $ 19.58
Restricted Stock [Member] | 1/3rd per year on grant-date anniversary [Member] |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |
Vesting Terms | 1/3rd per year on grant-date anniversary |
Number of Shares | 433 |
Weighted Average Grant- date Fair Value | $ 15.81 |
Restricted Stock [Member] | 1/3rd per year on grant-date anniversary [Member] |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |
Vesting Terms | 1/3rd per year on grant-date anniversary |
Number of Shares | 22 |
Weighted Average Grant- date Fair Value | $ 15.95 |
Restricted Stock [Member] | 1/3rd per year on grant-date anniversary [Member] |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |
Vesting Terms | 1/3rd per year on grant-date anniversary |
Number of Shares | 445 |
Weighted Average Grant- date Fair Value | $ 15.08 |
Restricted Stock [Member] | 1/3rd per year on grant-date anniversary [Member] |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |
Vesting Terms | 1/3rd per year on grant-date anniversary |
Number of Shares | 465 |
Weighted Average Grant- date Fair Value | $ 20.02 |
Restricted Stock [Member] | Share Based Compensation Award Tranche Two Stock |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |
Vesting Terms | 1/3rd per year on grant-date anniversary |
Number of Shares | 305 |
Weighted Average Grant- date Fair Value | $ 18.90 |
Restricted Stock [Member] | Share Based Compensation Award Tranche One |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |
Vesting Terms | 1/4th on the 1st grant-date anniversary and 3/4th on the 2nd grant-date anniversary |
Number of Shares | 567 |
Weighted Average Grant- date Fair Value | $ 15.00 |
Restricted Stock [Member] | Share Based Compensation Award Tranche Two Restricted Stock |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |
Vesting Terms | 1/3rd per year on grant-date anniversary |
Number of Shares | 280 |
Weighted Average Grant- date Fair Value | $ 15.00 |

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- Definition Description of award terms as to how many shares or portion of an award are no longer contingent on satisfaction of either a service condition, market condition or a performance condition, thereby giving the employee the legal right to convert the award to shares, to sell the shares, and be entitled to the cash proceeds of such sale. For example, vesting may be expressed as being 25 percent of the shares under option on each anniversary of the grant date. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (a)(1) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 + Details
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- Definition 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). + References 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=6415400&loc=d3e5070-113901 + Details
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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). + References 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=6415400&loc=d3e5070-113901 + 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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