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

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 123R

-Paragraph A240

-Subparagraph b(2)(c)

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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

Related Party Transactions (Details)			12 Months Ended	1 Months Ended
Related Party Transactions (Details)	Dec. 31, 2012 item	Dec. 31, 2011 item	Dec. 31, 2012 Restricted stock units	Dec. 31, 2012 Chief executive officer Stock option	Dec. 31, 2012 Chief executive officer Restricted stock units
Related Party Transactions
Number of principal stockholders for which chief executive officer serves as a general partner	1
Number of principal stockholders from whom the entity has leased office space		1
Related Party Transactions
Granted (in shares)				339,313
Granted (in shares)			192,308		192,308