Comprehensive Income - Schedule of Changes in Balances of Each Component of Accumulated Other Comprehensive Income (Detail) - Successor [Member] - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
Changes In Accumulated Other Comprehensive Income [Roll Forward]
Beginning Balance	$ 15,215	$ 220,283
Other comprehensive income before reclassifications	33,781	75
Amounts reclassified from accumulated other comprehensive income	9,016	(51,029)
Net current period other comprehensive income	42,797	(50,954)
Ending Balance	58,012	169,329
Unrealized Gains (Losses) on Available-for-Sale Securities [Member]
Changes In Accumulated Other Comprehensive Income [Roll Forward]
Beginning Balance	50,963	210,693
Other comprehensive income before reclassifications	51,562	33,554
Amounts reclassified from accumulated other comprehensive income	8,229	(51,002)
Net current period other comprehensive income	59,791	(17,448)
Ending Balance	110,754	193,245
Other Postretirement Benefit Plan, Defined Benefit [Member]
Changes In Accumulated Other Comprehensive Income [Roll Forward]
Beginning Balance	9,344	10,031
Other comprehensive income before reclassifications	0	0
Amounts reclassified from accumulated other comprehensive income	787	(27)
Net current period other comprehensive income	787	(27)
Ending Balance	10,131	10,004
Accumulated Translation Adjustment [Member]
Changes In Accumulated Other Comprehensive Income [Roll Forward]
Beginning Balance	(45,092)	(441)
Other comprehensive income before reclassifications	(17,781)	(33,479)
Amounts reclassified from accumulated other comprehensive income	0	0
Net current period other comprehensive income	(17,781)	(33,479)
Ending Balance	$ (62,873)	$ (33,920)