Investment Securities (Details 2) - USD ($) $ in Thousands	Sep. 30, 2017	Dec. 31, 2016
Unrealized Gains (Losses) on Available-For-Sale Securities
Amortized Cost	$ 455,057	$ 512,109
Unrealized Gains	14,478	13,408
Unrealized Losses	(877)	(2,762)
Estimated Fair Value	468,658	522,755
Corporate bonds
Unrealized Gains (Losses) on Available-For-Sale Securities
Amortized Cost	245,426	402,472
Unrealized Gains	38	285
Unrealized Losses	(45)	(87)
Estimated Fair Value	245,419	402,670
Other (including restricted)
Unrealized Gains (Losses) on Available-For-Sale Securities
Amortized Cost	107,823	32,488
Unrealized Gains	1	3
Unrealized Losses	(30)	(23)
Estimated Fair Value	107,794	32,468
Equity securities - strategic
Unrealized Gains (Losses) on Available-For-Sale Securities
Amortized Cost	101,808	77,149
Unrealized Gains	14,439	13,120
Unrealized Losses	(802)	(2,652)
Estimated Fair Value	$ 115,445	$ 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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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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