Long-Term Debt (Details) (Revolving credit facility, USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Revolving credit facility
Line of Credit Facility [Line Items]
Interest incurred	$ 2,090	$ 2,936	$ 4,146
Capitalized interest	935	1,026	627
Interest paid (net of capitalized interest)	$ 618	$ 1,498	$ 3,168
Weighted average interest rate	3.70%	2.30%	2.80%