Goodwill and Other Intangibles Additional Information (Details) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2014	Dec. 31, 2013
Business Acquisition [Line Items]
Goodwill	$ 64,493	$ 64,493
Credo [Member]
Business Acquisition [Line Items]
Goodwill	60,619
Credo [Member] | Patents [Member]
Business Acquisition [Line Items]
Goodwill and other intangible assets	448
Identified intangible assets acquired	590
Water Resource Company [Member]
Business Acquisition [Line Items]
Goodwill	3,874
Goodwill and other intangible assets	$ 1,681