Income Taxes (Reconciliation Of Unrecognized Tax Benefits) (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Reconciliation of Unrecognized Tax Benefits [Roll Forward]
Balance at January 1	$ 2,425	$ 1,864	$ 1,964
Additions due to merger with Frontier	0	22,577	0
Additions for tax positions of prior years	10,305	73	6
Reductions for tax positions of prior years	(89)	(204)	(106)
Settlements	0	(21,679)	0
Reductions for statute limitations	0	(206)	0
Balance at December 31	$ 12,641	$ 2,425	$ 1,864