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Financial Statements (Narratives) (Details) - USD ($) $ in Thousands	Mar. 31, 2019	Jan. 01, 2019	Dec. 31, 2018
New Accounting Pronouncements or Change in Accounting Principle
Operating lease right of use assets	$ 13,116
Lease liability current	3,304
Operating lease liability, noncurrent	9,812		$ 0
Accumulated other comprehensive loss	(21,704)		(22,191)
Retained earnings	$ 118,647		$ 114,324
ASU 2016-02
New Accounting Pronouncements or Change in Accounting Principle
Operating lease right of use assets		$ 13,585
Lease liability current		3,322
Operating lease liability, noncurrent		10,263
ASU 2018-02 \| Reclassified
New Accounting Pronouncements or Change in Accounting Principle
Accumulated other comprehensive loss		(633)
Retained earnings		$ 633