Accumulated Other Comprehensive Income - Changes in AOCI (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015
Changes in AOCI by component
Beginning balance	$ 33,457	$ 39,362	$ 29,729	$ 55,896
OCI before reclassifications	(918)	6,345	2,715	(4,997)
Amounts reclassified from AOCI	88	194	183	(4,998)
Net period OCI	(830)	6,539	2,898	(9,995)
Ending balance	32,627	45,901	32,627	45,901
Effective Portion of Cumulative Loss on Cash Flow Hedges
Changes in AOCI by component
Beginning balance	(338)	(360)	(65)	(97)
OCI before reclassifications	(136)	(71)	(504)	(538)
Amounts reclassified from AOCI	88	194	183	398
Net period OCI	(48)	123	(321)	(140)
Ending balance	(386)	(237)	(386)	(237)
Cumulative Unrealized Gain (Loss) on Available-for-Sale Securities
Changes in AOCI by component
Beginning balance	33,907	52,227	37,307	60,190
OCI before reclassifications	5,951	(1,857)	2,551	(4,424)
Amounts reclassified from AOCI				(5,396)
Net period OCI	5,951	(1,857)	2,551	(9,820)
Ending balance	39,858	50,370	39,858	50,370
Foreign Currency Translation
Changes in AOCI by component
Beginning balance	(112)	(12,505)	(7,513)	(4,197)
OCI before reclassifications	(6,733)	8,273	668	(35)
Net period OCI	(6,733)	8,273	668	(35)
Ending balance	$ (6,845)	$ (4,232)	$ (6,845)	$ (4,232)

Accumulated change in equity from transactions and other events and circumstances from non-owner sources, net of tax effect, at period end. Excludes Net Income (Loss), and accumulated changes in equity from transactions resulting from investments by owners and distributions to owners. Includes foreign currency translation items, certain pension adjustments, unrealized gains and losses on certain investments in debt and equity securities, other than temporary impairment (OTTI) losses related to factors other than credit losses on available-for-sale and held-to-maturity debt securities that an entity does not intend to sell and it is not more likely than not that the entity will be required to sell before recovery of the amortized cost basis, as well as changes in the fair value of derivatives related to the effective portion of a designated cash flow hedge.

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