Income Taxes (Deferred Tax Liabilities and Assets) (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2012	Dec. 31, 2011
Income Tax Disclosure [Abstract]
Current deferred income tax assets	$ 2,074	$ 3,277
Long-term deferred income tax assets	35,140	28,865
Total deferred income tax assets	37,214	32,142
Current deferred income tax liabilities	(239)	(297)
Long-term deferred income tax liabilities	(23,895)	(19,452)
Net deferred income tax asset	$ 13,080	$ 12,393