Common Stock Repurchase Plan (Details)	Dec. 31, 2012	May 16, 2007
Common Stock Repurchase Plan [Abstract]
Shares authorized to be repurchased (in shares)		721,598
Repurchase plan percentage of common stock outstanding (in hundredths)		5.00%
Number of shares available for repurchase (in shares)	624,739

The remaining number of shares authorized to be repurchased by an entity's Board of Directors under a stock repurchase plan.

No definition available.

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