Condensed Consolidated Statements of Cash Flows - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
Cash flows from operating activities:
Net cash provided by operating activities	$ 4,424	$ 2,543
Cash flows from investing activities:
Capital expenditures for property, plant and equipment	(6,083)	(5,074)
Capital expenditures for intangible assets	(316)	(39)
Purchase of other investments	(1,000)
Purchase of debt securities		(15,250)
Net proceeds from sale of assets		4,800
Net cash used in investing activities	(7,399)	(15,563)
Cash flows from financing activities:
Net proceeds from issuance of common shares	4,742	1,710
Changes in restricted cash		7,171
Repurchase and retirement of common shares	(26,464)
Excess income tax benefit on employee stock-based awards	222	57
Net cash provided by (used in) financing activities	(21,500)	8,938
Effect of exchange rate changes on cash	658	(2,949)
Net increase in cash and cash equivalents	(23,817)	(7,031)
Cash and cash equivalents at the beginning of the period	63,663	36,815
Cash and cash equivalents at the end of the period	$ 39,846	$ 29,784