v3.7.0.1

Net Income (Loss) Per Common Share - Antidilutive securities (Details) - $ / shares	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Earnings Per Share [Abstract]
Earnings per common share (in USD per share)	$ (0.13)	$ 0.08	$ (0.10)	$ 0.00
Income (loss) per common share (in USD per share)	$ (0.13)	$ 0.08	$ (0.10)	$ 0.00
Weighted-average number of common shares outstanding — basic	60,273,980	58,710,321	59,893,356	58,662,100
Total dilutive effect of outstanding share-based payments (in shares)	0	933,629	0	975,752
Weighted-average number of common shares outstanding — diluted	60,273,980	59,643,950	59,893,356	59,637,852
Equity Option [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities	5,238,465	7,376,383	5,633,489	7,358,351
Restricted Stock Units (RSUs) [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities	1,484,597	2,315,818	1,877,066	2,274,574
Performance Restricted Stock Units [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities	2,781,424	3,614,784	2,758,462	3,631,937
Employee Stock [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities	12,562	12,537	6,316	6,303

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- Definition

Securities (including those issuable pursuant to contingent stock agreements) that could potentially dilute basic earnings per share (EPS) or earnings per unit (EPU) in the future that were not included in the computation of diluted EPS or EPU because to do so would increase EPS or EPU amounts or decrease loss per share or unit amounts for the period presented.

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The amount of net income (loss) for the period per each share of common stock or unit outstanding during the reporting period.

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The amount of net income (loss) for the period available to each share of common stock or common unit outstanding during the reporting period and to each share or unit that would have been outstanding assuming the issuance of common shares or units for all dilutive potential common shares or units outstanding during the reporting period.

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Additional shares included in the calculation of diluted EPS as a result of the potentially dilutive effect of share based payment arrangements using the treasury stock method.

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The average number of shares or units issued and outstanding that are used in calculating diluted EPS or earnings per unit (EPU), determined based on the timing of issuance of shares or units in the period.

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