Carrying amount as of the balance sheet date, which is the cumulative amount paid and (if applicable) the fair value of any noncontrolling interest in the acquiree, adjusted for any amortization recognized prior to the adoption of any changes in generally accepted accounting principles (as applicable) and for any impairment charges, in excess of the fair value of net assets acquired in one or more business combination transactions.

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+ Details

Business Combination (Narrative) (Details) (USD $)	3 Months Ended	6 Months Ended		0 Months Ended	6 Months Ended
Business Combination (Narrative) (Details) (USD $)	Jun. 30, 2013	Jun. 30, 2013	Dec. 31, 2012	Jun. 22, 2012 Asset Acquisition [Member]	Jun. 30, 2013 Asset Acquisition [Member]
Business Acquisition [Line Items]
Closing date					Jun. 22, 2012
Cash purchase price				$ 100,000,000.0
Measurement Period				12 months
Purchase accounting adjustments, Goodwill					(14,766,000)
Goodwill	$ 295,094,000	$ 295,094,000	$ 295,094,000	$ 27,344,000
The forecasted future cash flows discounted rate	11.00%
Estimated weighted-average useful life of the acquired identifiable intangible assets		9 years 7 months 6 days