Gain on Sale of Asset (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended			3 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2014	Mar. 31, 2013
Property, Plant and Equipment [Line Items]
Gain on the sale of an office building and land	$ 1,234	$ 4,680	$ 0
Land [Member]
Property, Plant and Equipment [Line Items]
Gain on the sale of an office building and land	1,234			1,234
Building [Member]
Property, Plant and Equipment [Line Items]
Gain on the sale of an office building and land		$ 4,680			$ 4,680