Guarantor Financial Information (Details 4) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Condensed consolidating financial statements
Operating activities	$ 258,121	$ 220,576	$ 189,222
Investing activities	(318,997)	(29,043)	(476,033)
Financing activities	62,269	(175,636)	280,012
Net increase (decrease) in cash and cash equivalents	1,393	15,897	(6,799)
Beginning of period	26,623	10,726	17,525
End of period	28,016	26,623	10,726
Issuer
Condensed consolidating financial statements
Operating activities	178,769	128,146	92,521
Investing activities	(274,629)	10,544	(432,433)
Financing activities	97,384	(125,027)	333,703
Net increase (decrease) in cash and cash equivalents	1,524	13,663	(6,209)
Beginning of period	19,693	6,030	12,239
End of period	21,217	19,693	6,030
Guarantor Subsidiaries
Condensed consolidating financial statements
Operating activities	69,543	87,433	89,923
Investing activities	(34,749)	(34,121)	(36,822)
Financing activities	(34,987)	(51,122)	(53,691)
Net increase (decrease) in cash and cash equivalents	(193)	2,190	(590)
Beginning of period	6,886	4,696	5,286
End of period	6,693	6,886	4,696
Non-Guarantor Subsidiary
Condensed consolidating financial statements
Operating activities	5,842	2,406	0
Investing activities	(5,652)	(2,875)	0
Financing activities	(128)	513	0
Net increase (decrease) in cash and cash equivalents	62	44	0
Beginning of period	44	0	0
End of period	106	44	0
Adjustments/ Eliminations
Condensed consolidating financial statements
Operating activities	3,967	2,591	6,778
Investing activities	(3,967)	(2,591)	(6,778)
Financing activities	0	0	0
Net increase (decrease) in cash and cash equivalents	0	0	0
Beginning of period	0	0	0
End of period	$ 0	$ 0	$ 0

Amount of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. Excludes cash and cash equivalents within disposal group and discontinued operation.

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