Investment Securities (Details 2) - USD ($) $ in Thousands	Mar. 31, 2017	Dec. 31, 2016
Unrealized Gains (Losses) on Available-For-Sale Securities
Amortized Cost	$ 347,377	$ 512,109
Unrealized Gains	31,183	13,408
Unrealized Losses	(63)	(2,762)
Estimated Fair Value	378,497	522,755
Corporate bonds
Unrealized Gains (Losses) on Available-For-Sale Securities
Amortized Cost	231,838	402,472
Unrealized Gains	153	285
Unrealized Losses	(35)	(87)
Estimated Fair Value	231,956	402,670
Other (including restricted)
Unrealized Gains (Losses) on Available-For-Sale Securities
Amortized Cost	13,723	32,488
Unrealized Gains	0	3
Unrealized Losses	(28)	(23)
Estimated Fair Value	13,695	32,468
Equity securities - strategic
Unrealized Gains (Losses) on Available-For-Sale Securities
Amortized Cost	101,816	77,149
Unrealized Gains	31,030	13,120
Unrealized Losses	0	(2,652)
Estimated Fair Value	$ 132,846	$ 87,617

Amount before tax of unrealized gain in accumulated other comprehensive income (AOCI) on investments in debt securities classified as available-for-sale.

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-Publisher FASB
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