Condensed Consolidated Balance Sheets (Unaudited) (Parenthetical) - USD ($) $ in Thousands	Mar. 31, 2017	Dec. 31, 2016
Property and equipment
Accumulated depreciation	$ 47,544	$ 46,543
Stockholders’ Equity
Common Shares, par value (in dollars per share)	$ 0.015	$ 0.015
Common Shares, authorized (in shares)	233,333,000	233,333,000
Common Shares, issued (in shares)	93,377,000	93,105,000
Common Shares, outstanding (in shares)	93,377,000	93,105,000
Investments available for sale
Amortized cost	$ 1,732,058	$ 1,629,538
Fixed maturities
Investments available for sale
Amortized cost	1,619,677	1,497,186
Short-term investments
Investments available for sale
Amortized cost	$ 112,381	$ 132,352

Amount of accumulated depreciation, depletion and amortization for physical assets used in the normal conduct of business to produce goods and services.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 360
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=6391035&loc=d3e2868-110229

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.14)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Section S99
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-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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-Name Accounting Standards Codification
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