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Marketable Securities - Continuous Unrealized Loss Position (Details) $ in Thousands | Mar. 31, 2018 USD ($)
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Fair Value |
Less than 12 months | $ 14,202
12 months or greater | 1,100
Unrealized Loss |
Less than 12 months | (113)
12 months or greater | (1)
U.S. treasury debt securities |
Fair Value |
Less than 12 months | 1,980
12 months or greater | 1,100
Unrealized Loss |
Less than 12 months | (7)
12 months or greater | (1)
U.S. corporate debt securities |
Fair Value |
Less than 12 months | 12,222
12 months or greater | 0
Unrealized Loss |
Less than 12 months | (106)
12 months or greater | $ 0

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