Consolidated Statements of Income (Parenthetical) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Income Statement [Abstract]
Interest expense, related party interest	$ 0us-gaap_InterestExpenseRelatedParty	$ 0us-gaap_InterestExpenseRelatedParty	$ 217us-gaap_InterestExpenseRelatedParty

Amount of interest expense incurred on a debt or other obligation to related party.

No definition available.

Name:	us-gaap_InterestExpenseRelatedParty
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration