Short Term Borrowings (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended	6 Months Ended
Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013
Lines Of Credit Facility
Weighted daily outstanding amount	$ 26,874	$ 25,873	$ 27,435	$ 26,895
Weighted average interest rates	1.42%	1.34%	1.44%	1.37%

Average amount borrowed under the credit facility during the period.

No definition available.

Name:	us-gaap_LineOfCreditFacilityAverageOutstandingAmount
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration