Inventories - Schedule of Inventory (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Inventory Disclosure [Abstract]
Raw materials	$ 5,896us-gaap_InventoryRawMaterials	$ 6,697us-gaap_InventoryRawMaterials
Work-in-process	1,703us-gaap_InventoryWorkInProcess	1,553us-gaap_InventoryWorkInProcess
Finished goods	1,839us-gaap_InventoryFinishedGoods	2,799us-gaap_InventoryFinishedGoods
Total gross inventories	9,438us-gaap_InventoryGross	11,049us-gaap_InventoryGross
Raw materials	2,582emri_InventoryRawMaterialsReserve	3,150emri_InventoryRawMaterialsReserve
Work-in-process	435emri_InventoryWorkInProcessReserve	431emri_InventoryWorkInProcessReserve
Finished goods	382emri_InventoryFinishedGoodsReserve	1,111emri_InventoryFinishedGoodsReserve
Total reserve	3,399emri_InventoryNetReserve	4,692emri_InventoryNetReserve
Raw materials	3,314	3,547
Work-in-process	1,268	1,122
Finished goods	1,457	1,688
Total net inventories	$ 6,039us-gaap_InventoryNet	$ 6,357us-gaap_InventoryNet

Inventory finished goods reserve.

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Inventory net reserve.

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- Definition

Inventory raw materials reserve.

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- Definition

Inventory work in process reserve.

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Amount before valuation and LIFO reserves of completed merchandise or goods expected to be sold within one year or operating cycle, if longer.

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Carrying amount, net of valuation reserves and adjustments, as of the balance sheet date of merchandise or goods held by the company that are readily available for sale.

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Gross amount, as of the balance sheet date, of merchandise, goods, commodities, or supplies held for future sale or to be used in manufacturing, servicing or production process.

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Amount after valuation and LIFO reserves of inventory expected to be sold, or consumed within one year or operating cycle, if longer.

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Amount before valuation and LIFO reserves of raw materials expected to be sold, or consumed within one year or operating cycle, if longer.

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Carrying amount, net of valuation reserves and adjustments, as of the balance sheet date of unprocessed items to be consumed in the manufacturing or production process.

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Amount before valuation and LIFO reserves of merchandise or goods in the production process expected to be completed within one year or operating cycle, if longer.

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Carrying amount, net of reserves and adjustments, as of the balance sheet date of merchandise or goods which are partially completed. This inventory is generally comprised of raw materials, labor and factory overhead costs, which require further materials, labor and overhead to be converted into finished goods, and which generally require the use of estimates to determine percentage complete and pricing.

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