Consolidated Statements of Equity (Unaudited) - USD ($) $ in Thousands	Common Stock [Member]	Additional Paid-in Capital [Member]	Retained Earnings [Member]	AOCI Attributable to Parent [Member]	Parent [Member]	Noncontrolling Interest [Member]	Total
Balance (in shares) at Dec. 31, 2014	45,537
Balance at Dec. 31, 2014	$ 46	$ 742,006	$ 41,539	$ (8,668)	$ 774,923	$ 11,823	$ 786,746
Stock-based compensation		1,127			1,127		1,127
Exercise of options by employees and directors (in shares)	295
Exercise of options by employees and directors		2,704			2,704		2,704
Share exchange with Parent (in shares)	2,996
Share exchange with Parent	$ 3	$ 25,754			$ 25,757		25,757
Cash paid to non controlling interest						$ (228)	(228)
Cash dividend declared			$ (3,898)		$ (3,898)		(3,898)
Net income			$ 10,032		10,032	$ 235	10,267
Loss in respect of derivative instruments designated for cash flow hedge				$ 23	23		23
Change in unrealized gains or losses in respect of the Company's share in derivatives instruments of unconsolidated investment				(3,296)	(3,296)		(3,296)
Amortization of unrealized gains in respect of derivative instruments designated for cash flow hedge				(30)	(30)		(30)
Balance (in shares) at Mar. 31, 2015	48,828
Balance at Mar. 31, 2015	$ 49	$ 771,591	$ 47,673	(11,971)	807,342	$ 11,830	819,172
Balance (in shares) at Dec. 31, 2015	49,107
Balance at Dec. 31, 2015	$ 49	849,223	$ 148,396	$ (7,667)	990,001	$ 93,873	1,083,874
Stock-based compensation		842			842		842
Exercise of options by employees and directors (in shares)	213
Exercise of options by employees and directors		$ 4,195			$ 4,195		4,195
Cash paid to non controlling interest						$ (2,869)	(2,869)
Cash dividend declared			$ (15,472)		$ (15,472)		(15,472)
Net income			$ 29,271		29,271	$ 1,674	30,945
Loss in respect of derivative instruments designated for cash flow hedge				$ 21	21		21
Change in unrealized gains or losses in respect of the Company's share in derivatives instruments of unconsolidated investment				(3,179)	(3,179)		(3,179)
Amortization of unrealized gains in respect of derivative instruments designated for cash flow hedge				(24)	(24)		(24)
Balance (in shares) at Mar. 31, 2016	49,320
Balance at Mar. 31, 2016	$ 49	$ 854,260	$ 162,195	$ (10,849)	$ 1,005,655	$ 92,678	$ 1,098,333