Equity Compensation (Schedule of Equity Compensation Restricted Stock Valuation Assumptions) (Details) (Restricted Stock, USD $)	6 Months Ended
Jun. 30, 2014
Restricted Stock
Schedule of Share Based Payment Award Restricted Stock Valuation Assumptions [Abstract]
Dividends per share (quarterly amounts)	$ 0.05
Risk-free interest rate	1.50%

Share-based Compensation Arrangement by Share-based Payment Award, Restricted Stock Fair Value Assumptions, Expected Dividend Payments Per Share

No definition available.

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Namespace Prefix:	wern_
Data Type:	num:perShareItemType
Balance Type:	na
Period Type:	duration