CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS (Parenthetical) - USD ($) $ in Millions	Mar. 31, 2019	Mar. 31, 2018
Reconciliation of cash, cash equivalents and restricted cash and cash equivalents at end of period:
Cash and cash equivalents	$ 57	$ 52
Restricted cash and cash equivalents included in other current assets	97	70
Restricted cash and cash equivalents included in restricted trust and escrow accounts	161	304
Cash, cash equivalents and restricted cash and cash equivalents at end of period	$ 315	$ 426