Intangible Asset (Tables)

12 Months Ended

Dec. 31, 2012

Goodwill and Intangible Assets Disclosure [Abstract]

Intangible Asset, Net

The following table summarizes the intangible asset balance as of December 31, 2012 and 2011.

	AT DEC. 31,
(THOUSANDS)	2012		2011
Gross carrying amount	$	177,537	$	177,537
Accumulated amortization	56,992		43,942
Intangible asset	$	120,545	$	133,595

Expected Amortization Expense

The following table summarizes the amortization expense expected to be recognized during each year through 2017 and thereafter.

(THOUSANDS)
Expected amortization expense
2013	$	14,026
2014	$	14,931
2015	$	15,876
2016	$	16,864
2017	$	18,009
Thereafter	$	40,839