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.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Antidilution
-URI http://asc.fasb.org/extlink&oid=6505113

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Diluted Earnings Per Share
-URI http://asc.fasb.org/extlink&oid=6510752

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Contingent Stock Agreement
-URI http://asc.fasb.org/extlink&oid=6508534

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 260
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=6371337&loc=d3e3550-109257

Name:	us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount
Namespace Prefix:	us-gaap_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration

Net Loss Per Common Share (Details) - shares	12 Months Ended
Net Loss Per Common Share (Details) - shares	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Performance-based restricted stock awards, M356
Weighted-average anti-dilutive shares related to:
Antidilutive securities excluded from computation of earnings per share (in shares)	1,417,230
Outstanding Stock options
Weighted-average anti-dilutive shares related to:
Antidilutive securities excluded from computation of earnings per share (in shares)	6,569,000	4,148,000	5,941,000
Restricted stock awards
Weighted-average anti-dilutive shares related to:
Antidilutive securities excluded from computation of earnings per share (in shares)	1,202,000	519,000	847,000