Employee Stock Purchase Plan (Detail)
|
12 Months Ended |
|
Dec. 31, 2015
$ / shares
shares
|
|---|
| Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |
|
| ESPP Shares Issued |
2,977,712
|
| Prior To Two Thousand Thirteen [Member] |
|
| Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |
|
| ESPP Shares Issued |
2,755,337
|
| Price per ESPP Share Issued | $ / shares |
$ 13.67
|
| January 1 2014 To March 31 2014 [Member] |
|
| Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |
|
| ESPP Shares Issued |
52,718
|
| Price per ESPP Share Issued | $ / shares |
$ 12.66
|
| April 1 2014 To June 30 2014 [Member] |
|
| Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |
|
| ESPP Shares Issued |
38,679
|
| Price per ESPP Share Issued | $ / shares |
$ 14.23
|
| July 1 2014 To September 30 2014 [Member] |
|
| Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |
|
| ESPP Shares Issued |
32,573
|
| Price per ESPP Share Issued | $ / shares |
$ 17.14
|
| October 1 2014 To December 31 2014 [Member] |
|
| Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |
|
| ESPP Shares Issued |
20,221
|
| Price per ESPP Share Issued | $ / shares |
$ 24.95
|
| January 1 2015 To March 31 2015 [Member] |
|
| Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |
|
| ESPP Shares Issued |
24,368
|
| Price per ESPP Share Issued | $ / shares |
$ 22.76
|
| April 1 2015 To June 30 2015 [Member] |
|
| Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |
|
| ESPP Shares Issued |
15,750
|
| Price per ESPP Share Issued | $ / shares |
$ 33.77
|
| July 1 2015 To September 30 2015 [Member] |
|
| Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |
|
| ESPP Shares Issued |
18,984
|
| Price per ESPP Share Issued | $ / shares |
$ 32.27
|
| October 1 2015 To December 31 2015 [Member] |
|
| Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |
|
| ESPP Shares Issued |
19,082
|
| Price per ESPP Share Issued | $ / shares |
$ 33.42
|