Treasury Stock (Details)	Mar. 31, 2015	Dec. 31, 2014
Stockholders' Equity Note [Abstract]
Number of shares held in treasury	2,192,982us-gaap_TreasuryStockNumberOfSharesHeld	2,192,982us-gaap_TreasuryStockNumberOfSharesHeld

Number of shares held for each class of treasury stock.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 505

-SubTopic 30

-Section 45

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6405813&loc=d3e23239-112655

Name:	us-gaap_TreasuryStockNumberOfSharesHeld
Namespace Prefix:	us-gaap_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	instant