Schedule of Fair Value and Carrying Value of Assets and Liabilities (Detail) (USD $) In Thousands, unless otherwise specified	Jun. 30, 2014	Dec. 31, 2013	Jun. 30, 2013	Dec. 31, 2012
Minority Interest [Line Items]
Cash and cash equivalents	$ 65,891	$ 175,872	$ 88,669	$ 223,166
Other current assets	25,435	20,665
Property, plant and equipment, less accumulated depreciation of $380,683 and $353,428	441,156	414,257
Intangible assets, less accumulated amortization of $84,244 and $78,784	53,925	57,488
Other long-term assets	26,287	25,231
Total assets	1,161,346	1,194,797
Current liabilities	148,765	195,060
Total liabilities	594,602	640,399
KFPC
Minority Interest [Line Items]
Cash and cash equivalents	36,498	66,816
Other current assets	1,253	256
Property, plant and equipment, less accumulated depreciation of $380,683 and $353,428	35,264	12,912
Intangible assets, less accumulated amortization of $84,244 and $78,784	10,136	10,094
Other long-term assets	448	462
Total assets	83,599	90,540
Current liabilities	2,557	8,724
Total liabilities	$ 2,557	$ 8,724