Basis of Presentation (Details) - Primary beneficiary - USD ($) $ in Thousands	Jun. 30, 2015	Dec. 31, 2014
Variable Interest Entity
Liabilities of the deferred compensation plan	$ 11,504	$ 11,051
Assets held in the related rabbi trust	$ 15,706	$ 15,519

Aggregate carrying value as of the balance sheet date of the liabilities for deferred compensation arrangements payable after one year (or the normal operating cycle, if longer). Represents currently earned compensation under cash arrangements (such as a profit-sharing plan, rabbi trust, and employee contract--excluding equity-based arrangements) that is not actually paid until a later date.

No definition available.

Name:	us-gaap_DeferredCompensationCashbasedArrangementsLiabilityClassifiedNoncurrent
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant