CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS (USD $) In Thousands, unless otherwise specified	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014
Operating Activities:
Net income	$ 21,128us-gaap_ProfitLoss	$ 21,357us-gaap_ProfitLoss
Adjustments to reconcile net income to net cash provided by (used in) operating activities:
Depreciation	23,051us-gaap_Depreciation	23,816us-gaap_Depreciation
Amortization of intangibles	3,548us-gaap_AmortizationOfIntangibleAssets	4,436us-gaap_AmortizationOfIntangibleAssets
Stock-based compensation expense	2,629us-gaap_ShareBasedCompensation	3,906us-gaap_ShareBasedCompensation
Equity earnings, net of dividends related to earnings	141	1,033
Gain on remeasurement of previously held equity interest	11,622	0
Deferred income taxes	1,754us-gaap_DeferredIncomeTaxExpenseBenefit	6,830us-gaap_DeferredIncomeTaxExpenseBenefit
Other	(207)	(881)
Changes in operating assets and liabilities	(49,962)	(56,626)
Net cash provided by (used in) operating activities	(9,540)	3,871
Investing activities:
Capital expenditures	(51,315)	(63,817)
Acquisition of business, net of cash acquired	(24,442)	0
Return on equity investments	0	951
Proceeds from sale of fixed assets and other	2,237	2,125
Net cash used in investing activities	(73,520)	(60,741)
Financing activities:
Increase (decrease) in short-term debt, net	(2,416)	2,289
Borrowings on long-term debt	0	4,435
Principal payments on long-term debt	(1,891)us-gaap_RepaymentsOfLongTermDebt	(121)us-gaap_RepaymentsOfLongTermDebt
Payments of Debt Issuance Costs	0us-gaap_PaymentsOfDebtIssuanceCosts	(671)us-gaap_PaymentsOfDebtIssuanceCosts
Purchase of noncontrolling interests	1,262	0
Proceeds from exercise of warrants	0us-gaap_ProceedsFromWarrantExercises	4,571us-gaap_ProceedsFromWarrantExercises
Taxes withheld and paid on employees' share based payment awards	(992)	(866)
Other	(148)	(61)
Net cash provided by (used in) financing activities	(6,709)	9,576
Effects of exchange rate changes on cash and cash equivalents	16,933	969
Changes in cash and cash equivalents	(72,836)	(46,325)
Cash and cash equivalents at beginning of period	267,270	184,370
Cash and cash equivalents at end of period	$ 194,434	$ 138,045

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The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method.