Commitments and Contingencies - Approximate Aggregate Minimum Future Rental Payments Required (Details) ft² in Thousands, $ in Thousands	Dec. 31, 2015 USD ($) ft²	Dec. 31, 2013 ft²
Operating Leased Assets
2016	$ 14,091
2017	14,411
2018	12,909
2019	10,991
2020	8,981
Thereafter	6,991
Total	68,374
Sublease rentals due in 2016	700
Sublease rentals due in 2017	700
Sublease rentals due in 2018	700
Sublease rentals due in 2019	$ 600
Size of office space leased (sqft) \| ft²	7	15

Number of Leasable Square Feet

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Operating Leases, Future Minimum Payments Due, Future Minimum Sublease Rentals, Due in Four Years

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Operating Leases, Future Minimum Payments Due, Future Minimum Sublease Rentals, Due in Next Twelve Months

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Operating Leases, Future Minimum Payments Due, Future Minimum Sublease Rentals, Due in Three Years

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Operating Leases, Future Minimum Payments Due, Future Minimum Sublease Rentals, Due in Two Years

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Amount of required minimum rental payments for leases having an initial or remaining non-cancelable letter-terms in excess of one year.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 840
-SubTopic 10
-Section 55
-Paragraph 40
-Subparagraph (Note 3)
-URI http://asc.fasb.org/extlink&oid=6584154&loc=d3e38371-112697

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-Name Accounting Standards Codification
-Topic 840
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-Section 50
-Paragraph 2
-Subparagraph (a)
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Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due in the next fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due in the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 840
-SubTopic 20
-Section 50
-Paragraph 2
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=6453985&loc=d3e41502-112717

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 840
-SubTopic 10
-Section 55
-Paragraph 40
-Subparagraph (Note 3)
-URI http://asc.fasb.org/extlink&oid=6584154&loc=d3e38371-112697

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Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due in the fourth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due in the second fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due after the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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