Supplemental Guarantor Condensed Consolidating Financials - Condensed Consolidating Statements of Cash Flows (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2014	Mar. 31, 2013
Operating activities:
Net cash provided by operating activities	$ 16,179	$ 21,244
Investing activities:
Purchases of property and equipment	(2,430)	(1,360)
Purchase of investment	0	(1,886)
Net cash and cash equivalents used in investing activities	(2,430)	(3,246)
Financing activities:
Repayment of borrowings	(16,100)	0
Proceeds received from issuance of ordinary shares	4	0
Sale of subsidiaries		0
Net cash and cash equivalents used in financing activities	(16,096)	0
Effect of exchange rate changes on cash	(275)	(1,590)
Net (decrease) increase in cash and cash equivalents	(2,622)	16,408
Cash and cash equivalents:
Beginning of period	28,222	82,365
End of period	25,600	98,773
Parent [Member]
Operating activities:
Net cash provided by operating activities	(4)	1
Investing activities:
Purchases of property and equipment	0	0
Purchase of investment		0
Net cash and cash equivalents used in investing activities	0	0
Financing activities:
Repayment of borrowings	0	0
Proceeds received from issuance of ordinary shares	4
Sale of subsidiaries		0
Net cash and cash equivalents used in financing activities	4	0
Effect of exchange rate changes on cash	0	0
Net (decrease) increase in cash and cash equivalents	0	1
Cash and cash equivalents:
Beginning of period	1,528	1,527
End of period	1,528	1,528
Issuer / Guarantor Subsidiaries [Member]
Operating activities:
Net cash provided by operating activities	18,096	6,401
Investing activities:
Purchases of property and equipment	(2,009)	(1,045)
Purchase of investment		0
Net cash and cash equivalents used in investing activities	(2,009)	(1,045)
Financing activities:
Repayment of borrowings	(16,100)	0
Proceeds received from issuance of ordinary shares
Sale of subsidiaries		0
Net cash and cash equivalents used in financing activities	(16,100)	0
Effect of exchange rate changes on cash	0	0
Net (decrease) increase in cash and cash equivalents	(13)	5,356
Cash and cash equivalents:
Beginning of period	3,764	11,093
End of period	3,751	16,449
Non-guarantor Subsidiaries [Member]
Operating activities:
Net cash provided by operating activities	(1,913)	14,842
Investing activities:
Purchases of property and equipment	(421)	(315)
Purchase of investment		(1,886)
Net cash and cash equivalents used in investing activities	(421)	(2,201)
Financing activities:
Repayment of borrowings	0	0
Sale of subsidiaries		0
Net cash and cash equivalents used in financing activities	0	0
Effect of exchange rate changes on cash	(275)	(1,590)
Net (decrease) increase in cash and cash equivalents	(2,609)	11,051
Cash and cash equivalents:
Beginning of period	22,930	69,745
End of period	20,321	80,796
Eliminations [Member]
Operating activities:
Net cash provided by operating activities	0	0
Investing activities:
Purchases of property and equipment	0	0
Purchase of investment		0
Net cash and cash equivalents used in investing activities	0	0
Financing activities:
Repayment of borrowings	0	0
Sale of subsidiaries		0
Net cash and cash equivalents used in financing activities	0	0
Effect of exchange rate changes on cash	0	0
Net (decrease) increase in cash and cash equivalents	0	0
Cash and cash equivalents:
Beginning of period	0	0
End of period	$ 0	$ 0