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=6415400&loc=d3e5070-113901

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- Definition

The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet 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 (c)(2)(i)-(ii)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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- Definition

The number of equity-based payment instruments, excluding stock (or unit) options, that vested during the reporting period.

+ 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)(2)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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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.

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Stock Incentive Plans - Summary of Employee Restricted Common Stock Grant Awards (Details) - shares	1 Months Ended	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Restricted Common Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted during the year (in shares)		429,752
Unvested (in shares)	374,817	374,817	752,701
Vested (in shares)		741,690
Restricted Stock Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted during the year (in shares)		409,800
Unvested (in shares)	751,500	751,500	776,500
Vested (in shares)		366,400
Employees \| Restricted Common Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted during the year (in shares)		401,520	482,001	494,420	155,000	663,530
Unvested (in shares)	170,390	170,390	63,427	0	0	65,000
Vested (in shares)	200,797
Employees \| Restricted Common Stock \| Shares vesting in 2016
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unvested (in shares)	44,020	44,020	35,040	0	0	65,000
Employees \| Restricted Common Stock \| Shares vesting in 2017
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unvested (in shares)	126,370	126,370	28,387	0	0	0
Officers \| Restricted Stock Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted during the year (in shares)		409,800	395,900	432,300
Unvested (in shares)	400,600	400,600	350,900	0
Vested (in shares)	366,400