Related Party Transactions (Narrative) (Details)	3 Months Ended
Mar. 31, 2017 USD ($) h / yr item	Mar. 31, 2016 USD ($)	Dec. 31, 2016 USD ($)
Related Party Transaction [Line Items]
Outstanding accounts payable	$ 129,100,000		$ 192,275,000
AXIS Capital [Member]
Related Party Transaction [Line Items]
Due to related parties, current	752,000		808,000
Principal payments (including interest)	$ 69,000	$ 69,000
Weighted average interest rate	6.80%
Board of Directors Chairman [Member] \| Aircraft Lease [Member]
Related Party Transaction [Line Items]
Number of related party transaction agreements \| item	2
Number of leased aircrafts \| item	2
Aircraft lease amount payable, per month	$ 9,766
Aircraft hours available each year under lease \| h / yr	125
Cash payments	$ 60,000	$ 48,000
Outstanding accounts payable	$ 0		$ 0

Aircraft hours available each year under lease

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- Definition

Number of leased aircrafts.

+ References

No definition available.

+ Details

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- Definition

Number of related party transaction agreements.

+ References

No definition available.

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- Definition

Carrying value as of the balance sheet date of liabilities incurred (and for which invoices have typically been received) and payable to vendors for goods and services received that are used in an entity's business. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

+ References

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- Definition

Expenses incurred related to the lease of aircraft from outside third parties that are used in the entity's business operations.

+ References

No definition available.

+ Details

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Balance Type:	debit
Period Type:	duration

- Definition

Amount of the required periodic payments including both interest and principal payments.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.22)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 470
-Section 50
-Paragraph 3
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=6479336&loc=d3e64711-112823

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- Definition

Weighted average interest rate of debt outstanding.

+ References

No definition available.

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- Definition

Carrying amount as of the balance sheet date of obligations due all related parties. For classified balance sheets, represents the current portion of such liabilities (due within one year or within the normal operating cycle if longer).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08.(k)(1))
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 850
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=6457730&loc=d3e39549-107864

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.19(a))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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- Definition

Cash payments to suppliers for goods and services provided and to employees for services provided.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 25
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=66902209&loc=d3e3536-108585

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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- Details

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