Other Comprehensive Income (Loss) Components of Accumulated Other Comprehensive Income (Loss) (Details) - USD ($) $ in Thousands	6 Months Ended
Sep. 30, 2018	Sep. 30, 2017
Statement of Comprehensive Income [Abstract]
Other Comprehensive Income (Loss), Reclassification Adjustment from AOCI for Sale of Securities, Net of Tax	$ 0
Accumulated Other Comprehensive Loss, Available-for-sale Securities Adjustment, Net of Tax	(2,726)	$ (1,940)
Other Comprehensive Income (Loss), Reclassification Adjustment from AOCI for Investment Transferred from Available-for-sale to Equity Method, after Tax	721
Other comprehensive loss, net of taxes	(686)	508
Accumulated Other Comprehensive Loss, Available-for-sale Securities Adjustment, Net of Tax	$ (2,691)	$ (1,432)

Accumulated unrealized gain (loss), after tax, on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Amount after tax and reclassification adjustments, of appreciation (loss) in value of unsold available-for-sale securities. Excludes amounts related to other than temporary impairment (OTTI) loss.

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Amount after tax of reclassification adjustment from accumulated other comprehensive income for unrealized gain (loss) realized upon the sale of available-for-sale securities.

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Amount, after tax, of reclassification adjustment from accumulated other comprehensive income (loss) for unrealized gain (loss) of investment classified as available-for-sale transferred to equity method.

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